Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030339

Authors: Rocco Maria Comodo Silvia Pietramala Alessio Greco Riccardo Totti Giacomo Capece Giovanni Cepparulo Rocco De Vitis Vincenzo De Santis

Background: Total trapeziometacarpal (TMC) joint arthroplasty has emerged as a surgical option for selected patients with TMC osteoarthritis. The HORUS® prosthesis (Evolutis, France) is a novel uncemented modular implant featuring a threaded screw-in trapezial cup coated with porous titanium and a PEXEL-E liner (vitamin E-infused cross-linked polyethylene) with a semi-retentive articulation. The purpose of this study was to report preliminary clinical and radiographic outcomes of total TMC joint arthroplasty using the uncemented HORUS® prosthesis at 6-month follow-up. Methods: Eleven patients (8 women, 3 men; mean age 63.6 ± 10.1 years) with Eaton-Littler stage II–III TMC osteoarthritis and at least 6 months of unsuccessful conservative treatment underwent total TMC joint arthroplasty using the HORUS® prosthesis. All procedures were performed by a single surgeon through a dorso-radial approach. Clinical outcomes were assessed preoperatively and at 15 days, 1, 3, and 6 months postoperatively using the Visual Analogue Scale (VAS), QuickDASH questionnaire, and Kapandji opposition score. Standardized radiographs were assessed at 1, 3, and 6 months for component position, periprosthetic radiolucency, cup migration/loosening, and stem subsidence. Results: One intraoperative trapezial fracture (1/11; 9.1%) required conversion to trapeziectomy with suspension arthroplasty; this patient was excluded from the prosthetic outcome analysis. In the remaining 10 patients, mean VAS decreased from 8.7 ± 1.1 preoperatively to 0.3 ± 0.7 at 6 months, mean QuickDASH decreased from 66.2 ± 11.3 to 14.5 ± 7.6, and mean Kapandji score increased from 5.8 ± 0.8 to 9.2 ± 0.6. One minor postoperative complication occurred (flexor tendinopathy of the third and fourth digits at 4 weeks). No dislocation, infection, or radiographic evidence of component migration, stem subsidence, or periprosthetic radiolucency was detected during the 6-month observation period. Conclusions: In this small preliminary series, the HORUS® prosthesis was associated with marked short-term improvements in pain, disability, and thumb opposition. These data should not be interpreted as evidence of long-term implant survival or a reduced risk of loosening because the cohort was small and follow-up was limited to 6 months. Larger comparative studies with longer follow-up are required to assess durability, implant-related complications, and revision risk.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030338

Authors: Paul César Velásquez Porras Alicia Olinda Neyra Aranda Dimna Zoila Alfaro Quezada Digmer Pablo Riquez Livia Henri Emmanuel Lopez Gomez Roberto Carlos Dávila-Morán

Background: Day-to-day movement behavior may influence short-term glycemic variability in adults with type 2 diabetes, but free-living evidence integrating accelerometry with continuous glucose monitoring (CGM) remains limited. Objectives: This study examined whether daily moderate-to-vigorous physical activity (MVPA) and accelerometer-defined sedentary time were associated with 24-h within-day glycemic variability. Methods: In this longitudinal repeated-measures study, 140 adults with type 2 diabetes underwent 14 days of concurrent hip-worn ActiGraph GT3X+ accelerometry and FreeStyle Libre 2 CGM under free-living conditions in Lima, Peru. The primary outcome was a daily CGM-derived coefficient of variation (CV). Linear mixed-effects models separated within-person and between-person components, with Holm adjustment for the two primary within-person associations. Results: The fully adjusted primary analysis included 132 participants and 1728 participant-days. Higher within-person MVPA was associated with a lower daily CV (β = −0.27 percentage points per 10 min/day, 95% CI −0.45 to −0.09; Holm-adjusted p = 0.006), whereas greater accelerometer-defined sedentary time was associated with a higher CV (β = 0.05, 95% CI 0.01 to 0.09; Holm-adjusted p = 0.014). Secondary concurrent analyses showed favorable MVPA and opposite sedentary time associations for time in range, time above range, mean glucose, and glucose standard deviation (all false discovery rate q ≤ 0.018), with no statistically detectable association with time below range. Lagged associations were directionally consistent, but none remained statistically significant after multiplicity correction. Conclusions: Daily MVPA and accelerometer-defined sedentary times were associated with modest differences in within-day glycemic variability and concurrent CGM profiles. These observational findings do not establish causality or a specific exercise dose.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030337

Authors: Yinghong Liu Xiaoliang Qiu Dae-Sung Park

Background and Objectives: Ankle instructions during the active straight leg raise (ASLR) are not consistently standardized and may alter lumbopelvic measurements. This study tested whether a relaxed ankle, maximal active dorsiflexion (DF), and maximal active plantarflexion (PF) changed lateral abdominal muscle thickness and pressure biofeedback unit (PBU) responses during a standardized supine ASLR performed at 30° of hip flexion. Methods: Thirty-three healthy adults completed three trials per condition according to a pre-generated schedule containing all six possible condition orders. B-mode rehabilitative ultrasound imaging (RUSI) measured transversus abdominis (TrA), internal oblique (IO), and external oblique (EO) thickness at rest and during ASLR. Three end-expiratory images were acquired for each participant, condition, and state; each image was measured three times, and the three image means were averaged. Rest-to-ASLR changes yielded 99 participant-condition values. Pressure biofeedback unit (PBU) pressure was recorded at four prespecified events and analyzed at the trial level. Results: Across participant-condition means, TrA thickness was 2.44 ± 0.59 mm at rest and 2.66 ± 0.70 mm during ASLR; the largest observed mean was 4.46 mm under the study task, not a physiological maximum. DF increased the change in transversus abdominis thickness (ΔTrA) versus the relaxed ankle by 0.172 mm (95% CI, 0.077–0.267; p < 0.001) and total lateral abdominal wall change by 0.672 mm (95% CI, 0.413–0.931; p < 0.001). PF increased signed image-moment pressure deviation by 1.505 mmHg (95% CI, 0.985–2.025; p < 0.001). Conclusions: Ankle-position instructions changed ultrasound and PBU outcomes during ASLR. Standardizing ankle positioning instructions and image aggregation may improve measurement reproducibility.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030336

Authors: Cintia Gonçalves Rigoleto Santos Joilson Alves de Souza Leite Júnior Felipe J. Aidar Ângelo de Almeida Paz Teresa Figueiredo Luis Leitão

Background: Fibromyalgia (FM) is a chronic syndrome characterized by widespread musculoskeletal pain, fatigue, sleep disturbances, and cognitive and affective symptoms. Objectives: This study aimed to examine the acute effects of Resistance Training (RT) and Pilates on pain, functional impact, flexibility, and health-related quality of life in individuals with FM. Methods: In this randomized crossover pilot study, eight adults (7 females, 1 male; mean age: 48.5 ± 8.2 years) with a clinical diagnosis of FM participated. Each participant performed both RT and Pilates sessions in a randomized order. Outcomes were assessed at baseline and 24 h post-intervention using the Fibromyalgia Impact Questionnaire (FIQ), the 36-Item Short Form Health Survey (SF-36), the Visual Analog Scale (VAS) for pain, and the Wells sit-and-reach test (WELLS). Data were analyzed using two-way repeated-measures ANOVA and paired t-tests, with effect sizes (η2p and Cohen’s d) and 95% confidence intervals (95% CI). Statistical significance was set at p < 0.05. No formal sample size calculation was performed. Results: Participants presented a mean body mass index (BMI) of 27.4 ± 4.1 kg/m2 and time since diagnosis of 6.2 ± 3.1 years. Within-subject variations were observed following both interventions. FIQ scores decreased at 24 h after both RT and Pilates sessions (RT: 52.21 ± 18.61; Pilates: 45.50 ± 18.63; p = 0.038, η2p = 0.42, 95% CI [−12.5, −1.2]). Conclusions: Both Resistance Training and Pilates acutely reduced overall disease impact in individuals with fibromyalgia, with Pilates promoting superior acute gains in posterior chain flexibility.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030335

Authors: Efthymios Kyprianou Ploutarchos Saraslanidis George Tsalis Vassilios Panoutsakopoulos

Background: Curve sprinting in the 200 m dash entails distinct biomechanical requirements under strenuous anaerobic conditions that differ from sprinting on the straightway. This study aimed to examine possible relationships between anaerobic biomarkers (specifically, peak post-test blood lactate concentration; BLa) and step kinematic asymmetry, stance-phase biomechanics, and spring–mass model (SMM) variables at the curve-to-straight transition during a 200 m sprint. Methods: Sixteen adult male club- and national-level sprinters performed a maximal 200 m sprint test in this exploratory cross-sectional study. Kinematical data were recorded for the first step immediately after the geometric end of the curve, and peak BLa was measured at 3, 5, and 7 min post-test. Based on data normality, differences in inter-limb step parameters were examined using a paired t-test or Wilcoxon signed-rank test. Pearson’s and Kendall’s correlation coefficients evaluated the relationships between BLa and the biomechanical variables (significance level: a = 0.05). Results: Peak BLa was 16.16 ± 2.61 mmol/L and demonstrated no significant correlation (p > 0.05) with sprint time (24.89 ± 1.24 s). Only stride and step frequency during the outer-to-inner leg step was correlated (p < 0.05) with BLa. Furthermore, the step initiated by the outer leg had a larger length (p < 0.05) compared to the step length generated from the inner leg. Conclusions: These findings stem from the different roles between legs while handling the centripetal force requirements during curve sprinting. The outer leg generated a longer step to facilitate curve-to-straight transition, whereas the inner leg functioned primarily to stabilize and steer the body.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030334

Authors: Alessandro Guarnieri Valentina Presta Fabiana Laurenti Salvatore Mazzei Giuliana Gobbi Giancarlo Condello

Background: While the biomechanical, physiological, and nutritional determinants of table tennis (TT) performance have already been summarized, a dedicated synthesis of players’ anthropometric and motor characteristics is still lacking. This review aimed to synthesize current evidence across different ages, genders, and competitive levels. Methods: BASE, PubMed, ScienceDirect, Scopus, Semantic Scholar, and Web of Science databases were searched for study selection. Cross-sectional studies investigating the anthropometric and motor characteristics of healthy TT players aged 7–40 years were considered eligible. Results: Thirty-one studies were included. Eighteen studies focused on motor characteristics, seven on anthropometric traits, and six examined both. Conclusions: Adult male TT players predominantly exhibit an endomorph–ectomorph profile with greater lean mass, whereas females show an endomorph–ectomorph somatotype. Moreover, higher-ranked athletes generally display greater lean mass. Compared to specific strength-based sports athletes, TT players tend to have lower limb circumferences and lower lean and muscle mass, while showing higher body fat than specific speed- and agility-based sports. Higher-level players tend to demonstrate faster reaction and movement times, as well as superior change-of-direction abilities. Compared to other racket sports, they tend to exhibit superior coincidence-anticipation timing under high stimulus velocities and distinctive motor coordination. In terms of strength, TT players show proficiency in horizontal jumps and dynamic back strength, despite lower vertical explosive power. The identified characteristics provide a descriptive profile of table tennis players and may inform future longitudinal research investigating their potential relevance for talent identification and development.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030333

Authors: Mehmet Mesut Çelebi Atilla Çağatay Sezik

Background: Injuries are a major concern in professional football because they may reduce player availability and affect team performance. Injury risk may vary across different phases of the season in relation to changes in training and competition demands, recovery, and cumulative workload. Objectives: To describe the epidemiology of injuries in a professional football team over three consecutive seasons and to evaluate seasonal variations in injury characteristics and injury-related time-loss. Methods: This retrospective study analyzed 260 time-loss injuries sustained by 78 of 96 registered male first-team players (mean age 27.0 ± 4.5 years) from a professional football club in Türkiye over three consecutive seasons (2022–2023 to 2024–2025). Total team exposure was 33,609 player-hours (2409 match player-hours and 31,200 training player-hours). Injuries were classified according to injury setting, seasonal period, anatomical location, injury type, and injury-related time-loss. Exploratory generalized estimating equations (GEE) analysis accounted for repeated injuries within players. Results: A total of 260 injuries were recorded; 62.3% occurred during training and 37.7% during matches. The overall injury incidence was 7.7 per 1000 player-hours (95% CI, 6.8–8.7), with rates of 40.7 per 1000 match player-hours (95% CI, 33.0–49.6) and 5.2 per 1000 training player-hours (95% CI, 4.4–6.1). The groin–thigh–lower-leg region (52.7%) and the thigh (25.4%) were the most frequently affected anatomical sites, while muscle injuries accounted for 43.5% of all injuries. Estimated injury incidence was highest during the mid- and late-season (9.29 and 9.12 per 1000 player-hours, respectively) and lowest during the preparation period (2.55 per 1000 player-hours). Exploratory GEE analysis showed significant differences in injury counts across seasonal periods (Wald χ2 = 41.35, p < 0.001). Compared with the late season, injury incidence was lower during the preparation period (IRR 0.17, 95% CI 0.09–0.33; p < 0.001), whereas no significant differences were observed for the early or mid-season. Conclusions: Injury incidence was lowest during the preparation period and highest during the competitive season. Because exposure estimates were based on team-level rather than individual player-level data, these findings should be interpreted cautiously. Prospective multicentre studies with individual exposure data are needed.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030332

Authors: Shigeki Kubota Hideki Kadone Yukiyo Shimizu Masashi Yamazaki

Background and Objectives: The hybrid assistive limb (HAL) is a wearable robotic device used for rehabilitation that assists the voluntary movements of the user by detecting muscle action potentials and driving actuators positioned next to the hip and knee joints. Although upper-limb HAL training has been studied for brachial plexus injury (BPI), its electrophysiological influence remains unclear. The purpose of this study was to assess the electrophysiological influences of upper-limb HAL-assisted biofeedback (BF) training during elbow flexion rehabilitation in patients with BPI. Methods: Five patients with BPI (average age, 37.2 years) were enrolled after undergoing elbow flexor reconstruction through intercostal nerve-to-musculocutaneous nerve transfer. All participants received outpatient elbow flexion training with the upper-limb HAL at frequencies ranging from once weekly to once monthly. All patients started upper-limb HAL training when re-innervation was observed, and a biceps brachii muscle strength of grade 1 was achieved. Muscle activity was measured using surface electromyography in five patients during upper-limb HAL training, when the biceps brachii muscle strength was graded as Medical Research Council grades 1 and 2, to compare activity with and without HAL. Results: In five patients, electromyographic activity of the biceps brachii during elbow flexion reached 74.9 ± 22.7% of maximal contraction while using the HAL device, compared with 60.3 ± 16.7% without HAL assistance, indicating significantly greater muscle activation during HAL-assisted movement. Conclusions: Robotic BF training for elbow flexion with the upper-limb HAL may serve as a high-quality electromyographic rehabilitation approach for patients recovering from BPI.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030331

Authors: Giuseppe Caminiti

Cardiovascular diseases remain the leading cause of morbidity and mortality worldwide and continue to impose a substantial burden on individuals, healthcare systems, and society [...]

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030330

Authors: Annamaria Mancini Francesca Greco Daniela Vitucci Federico Quinzi Maria Grazia Tarsitano Loretta Francesca Cosco Andreina Alfieri Domenico Martone Sara Dei Rosa Ghirelli Luca Gentile Giulia Scalia Pasqualina Buono Gian Pietro Emerenziani

Background: Aging is characterized by functional decline in different organs and systems. The present study aimed to evaluate the effects of 6-month low-to moderate intensity supervised Social Dance (SD) program on muscular fitness, and clinical–biochemical and hematological parameters associated with healthy aging. Circulating CD34+ and serum antioxidant potential were assessed as exploratory outcomes. Methods: Seventy-nine elderly (aged > 65 years) were enrolled and randomized. Analyses included 49 participants who provided baseline and follow-up data and were assigned to the SD group (SDG, n = 24) or control group (CG, n = 25). Clinical–biochemical and hematological profiles, oxidative stress markers, circulating CD34+ cells, Physical fitness components and Physical Activity Scale for the Elderly (PASE) and EuroQol five-dimensional (EQ-5D) questionnaires were assessed at T0 and T1 to both groups. Results: Significant group × time interactions favored the SDG for HDL cholesterol (p=0.003), Hemoglobin (p = 0.031), and Hematocrit (p = 0.005). A significant increase in BAP (∆% = 33.3; p < 0.001) and PASE (∆%= 79.6 vs. 56.9; p < 0.05) were observed among the SDG; conversely, only a positive trend (∆% = 12.9 SDG vs. −5.1 CG) was observed for EQ-VAS at T1; these findings were not supported by significant group × time interaction. CD34+ cells increased significantly only in the CG. Isometric muscular performance declined in both groups. Conclusions: a 6-month SD program may provide beneficial effects on selected biochemical markers (i.e., a positive impact on HDL, hematological profile, antioxidant defenses) and perceived health outcomes in the elderly. However, it appears insufficient to preserve isometric muscular performance, suggesting that complementary resistance-based strategies may be needed to optimize neuromuscular adaptations.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030329

Authors: Ayoub Asadi Somayeh Bahrami Mostafa Bahrami Esmaeel Saemi

Background and Objectives: Sports performance is influenced by a variety of perceptual, cognitive, and motor factors. A better understanding of these factors can help coaches optimize training and improve athletic performance. The present study examined the acute effects of internal, external, and holistic attentional focus instructions on javelin-throwing performance under different visual conditions in novice performers. Methods: Twenty-four university students (12 females and 12 males; mean age: 21.50 ± 1.47 years) with no prior javelin-throwing experience completed 30 throws under six experimental conditions (5 throws per condition) based on three attentional focus instructions (internal, external, and holistic) and two visual conditions (vision-present and vision-absent) using a within-subject repeated-measures design. Throwing distance was measured as the primary performance outcome. Results: The results revealed significant main effects of both vision (F(1, 23) = 14.49, p = 0.001, ηp2 = 0.38) and attentional focus (F(2, 46) = 5.73, p = 0.006, ηp2 = 0.20). Overall throwing performance was superior when visual information was available compared to when vision was occluded (p = 0.001). In addition, both external and holistic focus conditions produced significantly greater throwing distances than the internal focus condition (p = 0.03; p = 0.04, respectively), with no significant differences observed between external and holistic focus (p > 0.05). No significant interaction was found between attentional focus and vision (F(2, 46) = 0.74, p = 0.48, ηp2 = 0.03), indicating that the effect of attentional focus did not significantly differ between the visual conditions. Conclusions: The present findings extend the attentional focus literature to a complex, whole-body ballistic skill, demonstrating that the adoption of external and holistic attentional focus instructions resulted in greater throwing distances than the internal focus condition in novice javelin throwers.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030328

Authors: Jorge E. Morais Tiago M. Barbosa

Background and Objectives: Intra-cyclic variation in swimming velocity is one of the variables most commonly used to assess swimming performance, providing simple, straightforward information for coaches and swimmers. Therefore, the main aim of this study was to assess the consistency and association between the two most commonly used methods for calculating the intra-cyclic variation in velocity in swimming (coefficient of variation—dv1; and range: the difference between the maximum and minimum instantaneous velocities—dv2). Methods: Twenty-one young butterfly swimmers (11 males and 10 females) with an average age of 17.3 ± 2.8 years were recruited for analysis. The measurements were done in the butterfly stroke at maximal velocities. The consistency and association criteria included the intraclass correlation coefficient (ICC) and simple linear regression between the two methods. Results: The ICC between dvs was excellent for the overall sample (ICC = 0.972, p < 0.001), males (ICC = 0.978, p < 0.001), and females (ICC = 0.955, p < 0.001). The linear regression between methods was very high (overall: R2 = 0.93, p < 0.001; males: R2 = 0.91, p < 0.001; females: R2 = 0.86, p < 0.001). Conclusions: Overall, coaches and researchers should be aware that although both methods yielded highly concordant results, they are based on different mathematical formulations and quantify distinct characteristics of the velocity signal. Therefore, their consistency and association should not be interpreted as mathematical equivalence or universal interchangeability.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030327

Authors: Michael C. Rumpf Johannes Jäger João Renato Silva Matthias Lochmann

Background and Objectives: The aim was to investigate the external load of different types of floaters and regular players in small-sided games (SSG) with different relative pitch sizes to inform the return-to-play process. Methods: Twenty-four professional soccer players from a Greek top-tier soccer club played SSG as regular players, internal floaters, and external floaters. Global-positioning units were utilized to investigate total distance (TD), as well as high-intensity running distances (HID), which was further divided into HID1 (15.0–19.9 km/h and HID2 (20.0–24.9 km/h). High-intensity running (HIR) was analyzed by distance and number of efforts (HIRnb) greater than 19.8 km/h. Velocity zones were categorized into zones such as 10.8–14.4 km/h (Zone3), 14.5–19.8 km/h (Zone4), 19.9–24.9 km/h (Zone5), >25 km/h (Zone6). Sprint metrics included number of sprints (Sprint/Nm) and sprint distance (Sprint/Dist). Acceleration bands were defined as high >4 m/s2 (ACC4), moderate 3–3.9 m/s2 (ACC3), and low 0–2.9 m/s2 (ACC2); and decelerations were defined as high <−4 m/s2 (DEC4), moderate −3.9–3 m/s2 (DEC3), and low −2.9–0 (DEC2 m/s2). All data were reported as relative value (standardized over a 1 min playing period). Results: Regular players showed the highest value, followed by internal floaters and external floaters for all variables, except for Zone5 distance. The majority of variables differed significantly between the regular players and the internal floaters except for TD, distance in Zone3 and Zone6, and number of ACC3, ACC4, and DEC4. ACC4 was the only variable found to be not significantly different between the regular players and the external floaters. In games with both floater types, internal floaters showed significantly higher values in all variables except for HIR, Zone6 distance, Sprint/Dist, Sprint/Nm, ACC3, ACC4, and DEC4. The comparison of external load variables between internal and external floaters when each player type was playing against regular players only revealed significantly higher values for all variables except for Sprint/Dist, Sprint/Nm, Zone6 distance, ACC3, and ACC4 for the internal floaters. Regression analyses were provided for all player types in the appropriated game format (RP with IF, RP with EF, RP with IF and EF). Conclusions: The on-field return-to-play process for individual players in the final stages incorporating SSG with different relative pitch sizes benefits from the utilization of different types of floaters. Increasing external load is ensured through starting with external floaters followed by internal floaters easing into the final role, the regular player role.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030326

Authors: Álvaro Farfán-Díaz Miguel Alarcón-Rivera Marcelo Andrade Oyarzun Daniel Tapia-Villanueva Exal Garcia-Carrillo Iván Molina-Márquez Rodrigo Yáñez-Sepúlveda Dario Barrera-González Felipe Montalva-Valenzuela

Background: Anthropometric body-composition assessment in youth soccer commonly relies on equations developed in different source populations and based on distinct body-composition models, potentially altering nutritional and sport-related interpretation. This study compared body-fat estimates from equations intended to report the same outcome, body fat percentage, but based on different operational models, and quantified muscle-mass outputs from anthropometric approaches targeting total-body skeletal, whole-body, and tissue-level muscle compartments in a cohort of Chilean male U-15 and U-16 players. Methods: This secondary cross-sectional method-comparison study analyzed anonymized anthropometric records collected in 2018 from 50 male players. Slaughter, Faulkner, Carter, Deurenberg, and Sloan–Siri estimates of body fat were compared, together with Poortmans, Lee, Doupe, and Kerr muscle-mass approaches. Absolute agreement among adiposity equations was evaluated using a two-way random-effects, absolute-agreement, single-measure ICC [ICC(A,1)] and Bland–Altman analyses. Muscle-mass approaches were compared with repeated-measures analysis; pairwise difference-versus-mean summaries across different muscle constructs were interpreted descriptively rather than as formal agreement tests. Sensitivity analyses excluded Deurenberg and examined a maturation-related Slaughter scenario. Results: Deurenberg yielded the highest body-fat estimate (18.97 ± 3.07%), followed by Slaughter (13.32 ± 3.35%), Faulkner (10.84 ± 1.40%), Sloan-Siri (8.01 ± 2.80%), and Carter (7.91 ± 1.49%). Global differences were large (χ2(4) = 182.96; p < 0.001; Kendall’s W = 0.915), and individual absolute agreement was low [ICC(A,1) = 0.157; bootstrap 95% CI 0.102–0.212]. Excluding Deurenberg did not remove the between-method differences (χ2(3) = 124.44; p < 0.001; W = 0.830). For muscle mass, mean estimates ranged from 25.11 ± 3.07 kg with Poortmans to 31.26 ± 4.94 kg with Doupe, with a significant method effect after Greenhouse–Geisser correction (p < 0.001). Conclusions: The adiposity equations yielded substantially different numerical estimates of the same reported outcome, body fat percentage, and showed low individual-level absolute agreement. Muscle-mass approaches also produced large numerical differences, partly expected because they target different compartments. Outputs from different equations or constructs should not be treated as numerically interchangeable. Because no criterion reference method was included, this study quantifies method dependence rather than validity and cannot identify the most accurate equation.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030325

Authors: Maria Luiza da Cruz Santos Pablo Augusto Garcia Agostinho Wanderson Matheus Lopes Machado Thalia Miranda Rufino Leonardo Silveira Goulart Silva Isabella Evangelista Leite Cláudia Eliza Patrocínio de Oliveira Édison Andrés Pérez-Bedoya Osvaldo Costa Moreira

Background: Executive functions (EFs) decline with aging, impacting functional independence. While resistance training (RT) is a promising non-pharmacological intervention, the optimal modality and duration for cognitive benefits remain unclear. Flywheel RT (FRT) imposes greater motor control and attentional demands than traditional RT (TRT), potentially enhancing EFs. Objective: To compare the effects of a 36-week FRT versus TRT program on executive function and serum insulin-like growth factor 1 (IGF-1) levels in healthy older women. Methods: This parallel-group randomized controlled trial allocated 64 older women (overall mean age 66.8 ± 4.6 years; FRT group: 68.0 ± 4.8 years; TRT group: 65.5 ± 4.1 years) to either FRT (n = 25) or TRT (n = 21) for two weekly sessions over 36 weeks. Executive function was assessed using the Victoria Stroop Test (inhibitory control), Digit Span Test (working memory), and Trail Making Test (cognitive flexibility). Serum IGF-1 was quantified via chemiluminescence. Intention-to-treat analyses with ANCOVA were performed. Results: After 36 weeks, both groups showed significant within-group improvements in inhibitory control (mean reduction from pre to post: FRT: 15.2 ± 10.4 to 14.8 ± 7.4 s; TRT: 20.4 ± 11.8 to 15.6 ± 7.3 s; p = 0.028, ηp2 = 0.38) and working memory (Digit Span Forward: FRT: 6.2 ± 1.7 to 7.9 ± 2.0; TRT: 6.7 ± 1.5 to 8.7 ± 1.8; p < 0.001, ηp2 = 0.84). The B/A ratio of the Trail Making Test improved significantly more in the FRT group (73.0 ± 65.2 to 87.5 ± 68.1 s) compared to the TRT group (67.3 ± 54.1 to 137.7 ± 83.6 s; group × time interaction: p = 0.001, ηp2 = 0.13). No significant changes in serum IGF-1 concentrations were observed in either group (FRT: 112.9 ± 25.4 to 115.3 ± 21.3 ng/mL; TRT: 104.7 ± 27.5 to 103.0 ± 28.9 ng/mL; p = 0.88, ηp2 = 0.002). Adherence was high (only 4 out of 46 participants did not complete all 72 sessions), and no severe adverse events were reported. Conclusions: Flywheel training appears particularly effective for enhancing cognitive flexibility, likely due to its higher cognitive-motor demands. The absence of significant changes in circulating IGF-1 suggests that the observed cognitive benefits may not be mediated by systemic endocrine pathways, although this does not exclude the possibility of local central nervous system adaptations or changes in other neurotrophic factors not assessed in this study.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030324

Authors: Julie Bastiere Aurélien Patoz Thibault Lussiana Marvin Subryan Cyrille Gindre Laurent Mourot

Background: Primitive reflex (PR) assessments based on the Institute for Neuro-Physiological Psychology (INPP) framework are increasingly used in developmental and athletic populations. However, the reproducibility of these observer-based assessments remains insufficiently documented. This study investigated the intra- and inter-rater reliability of subjective PR assessments and examined the potential influence of evaluator expertise in elite youth football athletes. Methods: Sixty-nine male youth football players from an elite academy (age: 18 ± 2 years) participated in this study. PR assessments included the Moro reflex, asymmetrical tonic neck reflex, symmetrical tonic neck reflex, and tonic labyrinthine reflex, evaluated using standardized INPP procedures (0–4 ordinal scoring scale). Intra-rater reliability was assessed by an experienced examiner across three testing sessions performed over six months. Inter-rater reliability was evaluated using standardized video recordings independently scored by two novice raters. Relative reliability was assessed using intraclass correlation coefficients (ICCs) with corresponding 95% confidence intervals (95% CIs), while absolute reliability was quantified using the standard error of measurement (SEM) and the minimal detectable change at the 95% confidence level (MDC95). Results: Good to excellent intra-rater relative reliability (ICC = 0.86–0.98; 95% CI = [0.81–0.99]) was observed, with SEM values of 0.1–0.6 and MDC95 values of 0.3–1.7 points. Moderate to excellent video-based inter-rater reliability was found (ICC = 0.69–0.99; 95% CI [0.56–0.99]), with SEM values of 0.1–0.7 and MDC95 values of 0.3–2.0 points. Pairwise comparisons among raters showed moderate to excellent relative reliability (ICC = 0.57–0.99; 95% CI [0.35–0.99]), with SEM values of 0.1–0.5 and MDC95 values of 0.2–1.3 points. Conclusions: Subjective PR assessments performed using the INPP framework demonstrated good to excellent intra-rater relative reliability and moderate to excellent video-based inter-rater relative reliability, together with generally low absolute measurement error in elite youth football athletes. These findings provide preliminary psychometric support for the use of standardized PR assessments in research and applied sport settings.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030323

Authors: Gaetano Raiola Giovanni Esposito Francesco Laterza Giuseppe Caminiti Rosario Ceruso Vincenzo Manzi

Background: Patellar tendon complaints and other tendon-related disorders are common in jumping sports; however, the relationship between recorded tendon problems, anthropometric characteristics, and neuromuscular performance in youth athletes remains poorly understood. This study explored the association between height, body mass, competitive age category, a retrospectively recorded history of tendon-related disorders, and jumping performance in youth volleyball players. Methods: Thirty-three male youth volleyball players competing in the Under-15, Under-17, and Under-19 categories participated in this cross-sectional study. For each athlete, Reach (maximum standing reach height), Vertec (maximum height attained during a maximal vertical jump), and vertical jump height, calculated as the difference between Vertec and Reach, were recorded. The presence or absence of tendon-related disorders was determined retrospectively from medical history information and club documentation. Data were analyzed using a multivariate general linear model, followed by univariate analyses and Bonferroni-adjusted post hoc comparisons. Results: Height showed a highly significant effect on the set of performance variables (Wilks’ λ = 0.066; p < 0.001), and competitive age category was also significantly associated with performance (Wilks’ λ = 0.655; p = 0.049). In contrast, neither body mass (p = 0.854) nor the tendon-related disorder variable (p = 0.293) demonstrated significant associations. Univariate analyses revealed significant effects of competitive age category on Vertec performance (p = 0.018) and vertical jump height (p = 0.008), but not on Reach (p = 0.542). Bonferroni-adjusted post hoc comparisons showed significant differences between the Under-19 and Under-15 categories for Vertec performance (p = 0.017), and between Under-19 and Under-15 (p = 0.007) as well as Under-17 and Under-15 (p = 0.034) for vertical jump height. Conclusions: Jumping performance in youth volleyball appears to be primarily influenced by anthropometric characteristics and developmental factors associated with competitive age category, whereas the dichotomous retrospective classification of tendon-related disorders adopted in the present study did not discriminate performance level. These findings highlight the importance of integrating functional, clinical, and training-load monitoring to better understand athletic development and tendon vulnerability.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030322

Authors: William J. Hanney Julia Chase Tysen Coates Christian Rodriguez-Rolas Michael Massaracchio Abigail W. Anderson

Background: Impaired lumbopelvic control and inefficient bending mechanics are associated with low back pain and functional limitations. The Founder Exercise is a movement retraining strategy intended to promote hip-dominant movement, trunk control, and postural awareness during forward bending. However, empirical evidence examining movement performance following Founder Exercise instruction is limited. This study examined immediate pre-to-post differences in hip hinge kinematics and movement confidence surrounding a standardized Founder Exercise instructional session in healthy adults. Methods: A within-subject pretest-posttest design was used. Thirty-three healthy adults (72.7% female; mean age, 25.1 ± 2.9 years) completed assessments of foot orientation, sagittal-plane joint kinematics, and movement confidence before and after a single Founder Exercise instructional session. Joint kinematics were assessed using two-dimensional video analysis. Paired-samples t-tests or Wilcoxon signed-rank tests, as appropriate based on the distributions of the paired differences, were used to evaluate the kinematic outcomes. The exploratory summed confidence score and individual ordinal confidence items were evaluated using Wilcoxon signed-rank tests. Holm adjustments were applied separately to the 11 kinematic comparisons and the 10 individual-item comparisons. Results: Statistically significant immediate pre-to-post differences were observed in several kinematic variables. Hip flexion increased from 80.7° ± 18.1° at pretest to 104.6° ± 14.3° at posttest, shoulder flexion increased from 62.8° ± 23.9° to 145.3° ± 13.9°, and craniovertebral angle decreased from 25.7° ± 12.9° to 11.2° ± 10.0° (all p < 0.001). The summed score from the unvalidated, study-specific confidence scale was higher at posttest (median = 49.0, IQR = 40.0–50.0) than at pretest (median = 40.0, IQR = 36.0–50.0; p < 0.001). After Holm adjustment of the individual ordinal-item analyses, statistically significant differences remained for five of the 10 items; all confidence findings were considered exploratory. No statistically significant differences were observed in knee flexion or ankle motion after Holm adjustment. Conclusions: A brief Founder Exercise instructional session was followed by immediate differences in selected two-dimensional hip hinge angles and higher exploratory movement-confidence scores in healthy adults. These findings do not establish changes in lumbopelvic control, muscle activation, spinal loading, movement efficiency, or clinical outcomes. Controlled studies incorporating direct measures of lumbar and pelvic motion, muscle activity, external forces, and clinically relevant outcomes are needed before biomechanical or clinical conclusions can be drawn.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030321

Authors: Justin A. DeBlauw Elissa Miller Kyle D. Heise Will K. Quinn Stephen J. Ives

Background and Objectives: Swimming has sprint and distance events, with current performance often driving selection rather than physiological characteristics of the athlete (e.g., muscle fiber type, blood lactate, etc.), especially among NCAA Division III swimmers, where these characteristics are unknown. We aimed to characterize the differences in estimated muscle fiber types (% fast twitch, %FT) and blood lactate (Blac) response to the maximal anaerobic lactate swim test (MANLT) between collegiate distance and sprint collegiate swimmers. Methods: Twenty-two college-aged (19.7 ± 1.0 yr) DIII swimmers (n = 13 sprint, n = 9 distance) performed an isokinetic muscular fatigue protocol to estimate their %FT, as well as their maximal and minimum Blac values and clearance rate (Blac recovery) (3 and 12 min post) after the MANLT was performed on two separate days (>48 h between). Results: There were no significant differences between sprint swimmers and distance swimmers in maximal Blac levels (11.6 ± 2.5 vs. 10.5 ± 3.4 mM, p = 0.38, d = 0.3), minimal Blac levels (9.3 ± 2.9 vs. 8.3 ± 3.3 mM, p = 0.45, d = 0.3), and percent decreases from 0 to 3 min (0.9 ± 13.1 vs. 9.9 ± 9.5, p = 0.09, d = 0.7), 0–12 min (15.4 ± 15.6 vs. 19.7 ± %, p = 0.52, d = 0.2), and 3–12 min (14.7 ± 12.5 vs. 11.04 ± 11.2%, p = 0.48, d = 0.3) Blac recovery. No significant differences were identified in estimated %FT between sprinters and distance swimmers (52 ± 6.4 vs. 45 ± 10.51, p = 0.056). Both extensor and flexor %FT estimations showed 69.2% and 66.7% accuracy in matching coach-identified event, with their respective estimated fiber type. A positive relation was identified between %FT knee flexor fibers and Blac (r = 0.44) and between %FT knee extensor fibers and Blac (r = 0.48) for all swimmers. Conclusions: This preliminary study suggests that athlete specialization is generally accurate to the physiology of the swimmer, namely anaerobic capacity and estimated fiber type.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030320

Authors: Janriek A. Bognot Eliza Clinton Erik W. Wilkins Richard J. Young Mina Rezaeian Jam Ryder Davidson George Alhwayek Reese Krider Jonathan A. Park Zachary A. Riley Brach Poston

Background: Transcranial direct current stimulation (tDCS) applied unilaterally to the cerebellum (c-tDCS) can improve several aspects of human motor performance. The purpose of the study was to examine the influence of dual source tDCS delivered bilaterally over the cerebellar cortices (dsc-tDCS) on the time to task failure (TTF) of a fatiguing contraction in young adults. Methods: The study utilized a double-blind, randomized, SHAM-controlled, within-subjects, crossover design, and participants were given either dsc-tDCS or SHAM stimulation in two different experiments held 7 days apart in a fully counterbalanced order. Every aspect of the two experiments was the same except the type of stimulation (dsc-tDCS or SHAM) delivered during the fatiguing contraction. The fatiguing contraction was executed with a precision grip at 15% of the maximum voluntary contraction (MVC) force, and participants were instructed to maintain the contraction for as long of time as possible. Results: The TTF and fatigue index were both similar for the dsc-tDCS and SHAM stimulation conditions. In addition, the electromyographic (EMG) activity, force error, and standard deviation (SD) of force measured during the fatiguing contraction were also not statistically different between the dsc-tDCS and SHAM stimulation conditions. Conclusions: The findings suggest that dsc-tDCS does not decrease the rate of progression of muscle fatigue.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030319

Authors: Sofiene Bouguerra Mohamed Amine Selmi Lotfi Bouguerra Yassine Negra Roland van den Tillaar Raouf Hammami

Background: Physical and technical development in youth soccer depends on the integration of neuromuscular and small-sided games (SSG) training. However, the influence of training sequence on adaptations remains unclear in prepubertal players. Therefore, this study aimed to compare the effects of performing neuromuscular training before or after SSG on physical fitness and soccer-specific performance in trained prepubertal soccer players. Methods: Twenty-two trained prepubertal male soccer players were randomly assigned to either neuromuscular training followed by SSG or SSG followed by neuromuscular training. Both groups completed a 6-week in-season intervention, including two weekly sessions, with each group performing 3 weeks of neuromuscular training and 3 weeks of SSG training in a different order. Physical fitness (back extensor strength, five-jump test, 10 m sprint, and Yo-Yo IR1) and soccer-specific performance (change of direction with ball and Loughborough Soccer Passing Test) were assessed before and after the intervention. Results: All 22 participants completed the intervention (n = 11 per group). Both groups demonstrated significant improvements over time in most physical fitness and soccer-specific performance variables (p < 0.01). However, significant group × time interactions indicated that the magnitude of improvement was consistently greater when neuromuscular training preceded small-sided games (p ≤ 0.041). Compared with the SSG-before-neuromuscular group, the neuromuscular-before-SSG group achieved larger improvements in back strength (+9.8% vs. +2.7%), five-jump test (+17.1% vs. +10.0%), 10 m sprint (−10.3% vs. −6.3%), Yo-Yo IR1 distance (+35.4% vs. +20.4%), change of direction with ball (−7.4% vs. −1.0%), and Loughborough Soccer Passing Test (−16.0% vs. −7.8%). Conclusions: Training sequence may influence the magnitude of short-term adaptations in prepubertal soccer players. Although both training orders improved performance, performing neuromuscular training before SSG resulted in greater improvements in several physical fitness and soccer-specific performance outcomes. These findings suggest that training order may represent an important factor in youth soccer training design; however, further research is required to confirm the consistency of this sequencing effect and to explore the mechanisms underlying these adaptations.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030318

Authors: Christopher J. Cleary Olivia Federico Lexy N. Farrington Nicholas S. Dombrowski Christopher D. Bernard Zachary D. Denton Bryan G. Vopat Ashley A. Herda

Background and Objectives: Strength deficits are extremely common following anterior cruciate ligament reconstruction (ACLR). These deficits may be further impacted by concomitant meniscus repair during ACLR. However, there remains limited evidence investigating the effect of meniscus repair on lower-limb strength after ACLR, and particularly if there are between-sex differences in strength after ACLR with and without meniscus repair. Therefore, the purpose of this study was to investigate sex-specific differences in meniscus repair during ACLR on quadriceps and hamstring isometric strength. Methods: Eighty-five (37 females; 19.0 ± 6.6 years old) patient charts were retrospectively evaluated after undergoing ACLR. Variables documented included meniscal status, maximal isometric quadriceps and hamstring strength of the operative (OP) and non-operative (NOP) legs. Three separate 3-way [leg (OP vs. NOP) × sex (males vs. females) × meniscus repair status (yes vs. no)] mixed-factorial analyses of variance (ANOVA) assessed differences in quadriceps and hamstring strength, and the hamstring-to-quadriceps strength ratio (H:Q), at an alpha level of p ≤ 0.05. Results: For H:Q there was a sex by meniscus repair status interaction (p = 0.007). Females who underwent meniscus repair had lower H:Q (18.2%) than those without. Females without meniscus repair had a 20.3% greater H:Q than males without meniscus repair. Males had greater quadriceps strength than females (mean difference ± standard error; 0.58 ± 0.28 N∙kg−1) and the NOP leg was stronger than OP for quadriceps (0.34 ± 0.08 N∙kg−1) and hamstring (0.14 ± 0.04 N∙kg−1) strength across sex. Conclusions: These findings suggest that the H:Q ratio differed according to sex and meniscus repair status. Further, there was a between-limb difference for strength in the quadriceps and hamstrings along with sex-related differences in strength. However, meniscus repair status did not influence raw strength values.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030317

Authors: Dimitrios Lytras Ioannis Algiounidis Vasileios Georgoulas Konstantinos Kasimis Georgia Maria Kamparoudi Georgios Tsigaras Georgia Vergidou Nikolaos Sidiropoulos Georgia Tarfali Ilias Kallistratos Paris Iakovidis

Background: Tibial bone stress injury (TBSI) with associated bone marrow edema (BME) is a common and clinically challenging condition in athletes, often requiring prolonged load restriction and delayed return to sport. Evidence for adjunctive interventions that improve both symptoms and MRI-derived recovery remains limited. The aim of this study was to investigate whether adding Functional Magnetic Stimulation (FMS) to standardized rehabilitation improves pain, function, and MRI-derived outcomes over 16 weeks in athletes with MRI-confirmed TBSI. Materials and Methods: Forty athletes with Fredericson grade 2–3 TBSI were randomized to FMS plus rehabilitation (n = 20) or rehabilitation alone (n = 20). Both groups completed a 4-week load-based rehabilitation program, while the FMS group additionally received eight 30 min FMS sessions at 40 Hz. Outcomes were assessed at baseline, 4 weeks, and 16 weeks. The primary outcome was activity-related pain (NPRS), while secondary outcomes included lower-limb function (LEFS-GR), BME extent, and Fredericson grade. Continuous outcomes were analyzed using two-way mixed ANOVA, whereas Fredericson grade was analyzed using an ordinal generalized estimating equation model. The level of statistical significance was set at p < 0.05. Results: Groups were comparable at baseline. Significant group × time interactions favored FMS for NPRS, F(2, 76) = 12.46, p < 0.001, η2p = 0.247; LEFS-GR, F(1.08, 41.09) = 81.56, p < 0.001, η2p = 0.682; and BME extent, F(1.44, 54.85) = 49.33, p < 0.001, η2p = 0.565. At 16 weeks, the FMS group showed lower NPRS scores, higher LEFS-GR scores, and lower BME extent than controls. Fredericson grade also showed a significant group × time effect, Wald χ2(2) = 20.38, p < 0.001. The FMS group had significantly lower cumulative odds of classification in a higher Fredericson grade at 4 weeks (OR = 0.045, 95% CI: 0.012–0.163, p < 0.001), whereas the corresponding difference at 16 weeks remained directionally favorable but did not reach statistical significance (OR = 0.033, 95% CI: 0.001–1.029, p = 0.052). Conclusions: The addition of FMS to load-based rehabilitation was associated with greater clinical and functional improvements, greater reductions in BME extent, and a more favorable longitudinal trajectory in MRI severity classification than rehabilitation alone in athletes with TBSI. However, because the study did not include a sham-FMS condition and participants could not be blinded, the self-reported pain and functional outcomes should be interpreted cautiously. FMS may represent a useful adjunct to structured rehabilitation, although sham-controlled and longer-term studies should determine its effects on return-to-sport progression and recurrence risk.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030316

Authors: Matteo Vitarelli Domenico Mario Giamundo Alberto Grossi Giuseppe Caminiti Gabriele Morganti Francesca Strassoldo di Villanova Bruno Ruscello Elvira Padua Maurizio Volterrani Valentina Morsella Marco Alfonso Perrone Vincenzo Manzi Gennaro De Rosa Lorenzo Loffredo Enrico Maggio

Isometric resistance training (IRT) has emerged as a promising non-pharmacological intervention for blood pressure (BP) management. Although current hypertension guidelines primarily recommend aerobic and dynamic resistance exercise, growing evidence indicates that IRT is an effective, feasible, and time-efficient alternative. This narrative review summarizes the current evidence on the efficacy, physiological mechanisms, and clinical applications of IRT. We reviewed randomized controlled trials, systematic reviews, and meta-analyses evaluating the effects of different IRT modalities, including isometric handgrip (IHG), isometric wall squat (IWS), and isometric leg extension (ILE), on BP in normotensive individuals, patients with hypertension, and those with cardiovascular disease. IRT consistently reduces resting systolic BP by approximately 5–8 mmHg and diastolic BP by 3–4 mmHg; these effects may approach those reported with first-line antihypertensive therapy and potentially be equivalent to those of other exercise modalities. These benefits have been demonstrated across normotensive and hypertensive populations and appear largely independent of age, sex, medication use, and the muscle groups involved. Preliminary evidence also supports the feasibility and safety of appropriately prescribed IRT in selected patients with ischemic heart disease and heart failure with preserved ejection fraction. Proposed mechanisms include improvements in endothelial function, nitric oxide bioavailability, autonomic regulation, oxidative stress, arterial baroreflex sensitivity, and myocardial efficiency. IRT has emerged as an effective, safe, and practical adjunct to lifestyle modification for BP control, particularly in older adults and individuals with limited ability to perform conventional exercise. However, current evidence derives from relatively small studies with limited follow-up; further large-scale randomized trials are needed to define the optimal exercise prescription, clarify the underlying mechanisms, and establish the role of IRT in patients with cardiovascular disease.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030314

Authors: Luis Alfonso Arráez-Aybar Carlos Miquel García-de-Pereda-Notario Luis Palomeque-Del-Cerro Juan José Montoya-Miñano

Background: The acromiohumeral distance (AHD) is a widely used imaging parameter for evaluating the subacromial region and shoulder function. Traditionally, it has been interpreted as a static anatomical measurement reflecting the available subacromial space and associated with rotator cuff pathology, superior humeral migration, and subacromial impingement. However, inconsistent relationships between AHD, symptoms, and function suggest that purely structural interpretations may be insufficient. Objectives: To propose a systems-based functional morphology framework that reinterprets AHD as an emergent functional state variable reflecting the instantaneous state of the glenohumeral system. Methods: A conceptual synthesis integrated evidence from shoulder biomechanics, functional morphology, movement science, connective tissue research, systems theory, and personalized neuromusculoskeletal modelling. Structural, connective tissue, neuromuscular, and mechanical determinants of AHD were integrated within a multilevel systems perspective. Results: The proposed framework conceptualizes AHD as emerging from the dynamic interaction of four organizational domains: structural constraints, connective tissue properties, neuromuscular regulation, and mechanical context. Rather than representing a fixed anatomical space, AHD is interpreted as a potential systems-level functional biomarker whose value varies according to the functional state of the glenohumeral system. This perspective explains the variability observed across imaging studies and the frequent discordance between structural findings, symptoms, and functional outcomes. Conclusions: Reframing AHD as an emergent functional state variable provides a theoretical basis for integrating anatomy, biomechanics, movement behavior, and neuromuscular control within personalized shoulder assessment. This systems-based perspective may help bridge the traditional gap between structural imaging and clinical presentation while supporting future developments in precision rehabilitation and subject-specific computational modelling.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030315

Authors: Domenico Di Fonza Gloria Di Claudio Gianmaria Colantuono Lorenzo Persichini Nicola Cerulo Benedetta Sangregorio Andrea Buonsenso Giovanni Fiorilli Giuseppe Calcagno Alessandra di Cagno

Background: The latissimus dorsi (LD) is a primary muscle involved in pulling exercises used in resistance training, contributing to shoulder extension, adduction and internal rotation, with relevance to athletic performance, injury prevention and rehabilitation as well as to upper-body aesthetics. Aim: to identify which exercise configurations are most consistently associated with greater latissimus dorsi electromyographic (EMG) amplitude. Methods: This SANRA-informed narrative review synthesized surface and high-density EMG evidence across major pulling exercises, for the lat pull-down, pullover, seated row, barbell row, bent-over row and pull-up. Twenty-three eligible studies were included and appraised using a six-criterion methodological checklist. Results: In the lat pull-down, an anterior bar path was the configuration most consistently associated with greater LD EMG amplitude, whereas the effects of grip width were inconsistent. In the seated row, a narrower grip and a lower shoulder-abduction angle were each associated with greater LD amplitude in separate studies; these two variables have not been tested in combination and should not be read as a single validated configuration. Among rowing variants, the inverted row produced the highest LD amplitude in a single, small preliminary study that requires replication. Pull-up variations showed broadly similar LD activation across grip configurations, while the pullover appeared to preferentially activate the pectoralis major rather than selectively target the LD. Conclusions: Current evidence tentatively supports the anterior lat pull-down and, within the seated row, a narrower grip and a lower shoulder-abduction angle (evaluated independently) as the configurations most consistently associated with greater LD EMG amplitude; these findings reflect acute EMG amplitude rather than longitudinal training outcomes and should be treated as an evidence-informed starting point rather than a definitive exercise prescription. Across pulling exercises, the humerus-to-trunk relationship may be a key biomechanical determinant of muscular load distribution.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030313

Authors: Karol Czyż Krzysztof Kasicki Łukasz Rydzik Winicjusz Sokół Julita Kalinowska Andrzej Kędra Jarosław Jaszczur-Nowicki

Background: Rugby union and rugby league are among the most physically demanding contact team sports, in which playing positions impose distinct physical requirements. The aim of the review was to collect and synthesize available data on positional differences in physical fitness between forwards and backs in adult male rugby players. Methods: The systematic review was conducted in accordance with PRISMA 2020 and SWiM guidelines and was prospectively registered in the OSF database (10.17605/OSF.IO/E4Y37). Four electronic databases were searched: PubMed, SPORTDiscus, Web of Science, and Scopus up to June 2026. The search identified 3058 records, which were reduced to 1343 after language and document-type limits and then screened. Eligibility criteria were applied within the PICOs framework. Methodological quality was assessed using JBI Critical Appraisal Checklists and the AXIS tool as a validation instrument. Due to considerable methodological heterogeneity, narrative synthesis with directional meta-synthesis was applied. Results: Thirty-seven studies were included (n > 2000 players; 15 countries; 1996–2025). Forwards achieved higher values of absolute muscular strength and power, body mass, and sprint momentum, whereas backs performed better in sprint tests (10–50 m), maximum sprint velocity, aerobic fitness (VO2max, Yo-Yo IRTL1), CMJ height, and relative power. Following normalization to body mass, positional differences in strength and power were attenuated or reversed. In the only study that isolated the change in direction deficit, no clear positional difference was observed. Conclusions: Body mass appears to be the principal explanatory factor underlying positional differences in absolute strength and power. Position-specific fitness profiles are observable as early as the U20 category and become more pronounced with increasing competitive level. Strength and conditioning coaches should compare positional groups using body mass normalized ratio or, where justified, allometrically scaled measures rather than absolute values.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030312

Authors: Shinya Kishi Yuuji Kimura Takao Minami

Background and Objectives: Efficient landing shock attenuation is important for both athletic performance and lower-extremity injury prevention in youth soccer players. Although landing biomechanics and change-of-direction (COD) performance have been widely investigated, the relationship between field-based COD performance and landing impact characteristics remains unclear. This study aimed to examine the relationships between linear sprint performance, COD performance, and landing impact during a standardized single-leg forward drop jump landing task in junior soccer players. Methods: Thirty-six junior soccer players (22 boys and 14 girls; 10–12 years) participated in this cross-sectional study. Linear sprint performance and COD performance were assessed using a 30 m sprint test and a 30 m zigzag run test, respectively. Landing impact was evaluated during a standardized single-leg forward drop jump landing task using a force plate. Body weight-normalized peak vertical ground reaction force (peak vGRF, %BW) was calculated for each trial, and the average of the final five successful trials was used for analysis. Relationships between performance measures and body weight-normalized peak vGRF were examined using Spearman’s rank correlation coefficients and partial Spearman correlation analyses adjusted for sex. Results: No significant correlation was observed between 30 m sprint performance and body weight-normalized peak vGRF (ρ = 0.106, p = 0.537). In contrast, 30 m zigzag run performance showed a moderate positive correlation with body weight-normalized peak vGRF (ρ = 0.401, p = 0.015), indicating that poorer COD performance was associated with greater landing impact. This association remained significant after adjustment for sex (partial ρ = 0.474, p = 0.004). Conclusions: These findings suggest that landing impact characteristics may represent one biomechanical factor associated with COD performance. Although the observed association was moderate, field-based COD assessments may provide practical information regarding landing impact characteristics. Future studies should incorporate biological maturation, COD deficit, and additional biomechanical variables to further clarify these relationships.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030311

Authors: Guilherme Eustáquio Furtado Maria Inês Marques António Rodrigues Sampaio Daniel Duarte Susana Ramos Eduardo Carballera Marta Sevilla-Sanchez Edson Eduardo Sónia Mateus Patrícia Coelho Francisco Rodrigues

Addictive behaviours are associated with substantial neurobiological, psychological, and behavioural impairments. Exercise training has emerged as a potential complementary strategy in addiction treatment; however, the characteristics of exercise interventions and their associated outcomes remain insufficiently characterized. This scoping review (ScR) was conducted according to the Joanna Briggs Institute methodology and reported in accordance with the PRISMA-ScR guidelines. Searches were conducted across three electronic databases for studies published between January 2015 and March 2025. Eligible studies investigated structured exercise training interventions in individuals with substance-related or behavioural addictions. Data were extracted regarding study characteristics, addiction type, exercise modality, FITT parameters, and neurobiological, biochemical, psychological, behavioural, and addiction-related outcomes. Five human intervention studies met the inclusion criteria, all addressing substance-related addictions, including alcohol use disorder, methamphetamine use disorder, and polysubstance dependence. Three studies evaluated acute exercise interventions, whereas two investigated structured exercise programmes lasting 8–12 weeks. Aerobic exercise was the most frequently investigated modality, although combined aerobic and resistance training, yoga, cycling, soccer-based exercise, circuit training, and functional exercise were also identified. Exercise intensity ranged from moderate to vigorous, with substantial variability in frequency, session duration, intervention period, and reporting of progression, supervision, and adherence. Reported outcomes included dopamine-related measures, mood, anxiety, depressive symptoms, self-esteem, affect, and craving. The available evidence suggests potentially relevant effects of exercise across neurobiological, psychological, and addiction-related domains, but the limited number and heterogeneity of studies preclude conclusions regarding the effectiveness of specific exercise prescriptions. The current evidence base on structured exercise training in addictive behaviours remains limited and heterogeneous and is restricted, among the eligible intervention studies identified, to substance-related addictions. Exercise may represent a promising complementary approach, but evidence is insufficient to establish optimal exercise modalities, FITT prescriptions, or sustained clinical benefits. Future research should prioritize adequately powered longitudinal randomized controlled trials, standardized reporting of exercise prescription and adherence, and comprehensive assessment of clinically relevant addiction-related outcomes.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030310

Authors: Yemin Han Yiqing Xie Zhen Zhang Amador García-Ramos

Objective: This article reports the prespecified boxing-specific component of a randomized controlled trial comparing velocity-based resistance training (VBT) with percentage-based training (PBT) in collegiate boxers. Boxing-specific performance was specified as a parallel primary outcome domain in the original ethics-approved protocol, although no single boxing-specific measure was designated as the sole primary endpoint; the five measures are therefore reported as prespecified exploratory outcomes. Methods: The trial was designed before participant recruitment to address two parallel research objectives: changes in general lower-limb performance and changes in boxing-specific performance. Twenty-eight male collegiate boxers were randomly allocated to VBT (n = 14) or PBT (n = 14). Results for lower-limb strength, jumping, and sprinting from the same trial have been reported previously. The present report focuses on lead and rear straight-punch (LSP and RSP) force and continuous-punch (CP) frequency over 10 s, 30 s, and 1 min. Both groups were prescribed the back squat, Bulgarian split-squat, and deadlift twice weekly for eight weeks. PBT participants completed four sets of five repetitions at 70% of one-repetition maximum (1RM), whereas VBT participants were prescribed four sets using the velocity associated with 70% 1RM and ended each set at 10% velocity loss. Results: The between-group differences in mean change, calculated as VBT minus PBT, were 6.97 kg for lead straight-punch force (95% CI: 0.40 to 13.54), 7.21 kg for rear straight-punch force (95% CI: 3.56 to 10.86), 4.47 punches·10 s−1 for 10 s continuous-punch frequency (95% CI: 0.33 to 8.62), 5.05 punches·30 s−1 for 30 s continuous-punch frequency (95% CI: 0.14 to 9.96), and −2.65 punches·min−1 for 1 min continuous-punch frequency (95% CI: −13.97 to 8.67). Conclusions: Greater mean improvements in straight-punch force and short-duration continuous-punch performance were observed in the VBT group, although the precision of several estimates was limited and the findings should be interpreted cautiously because multiple exploratory outcomes were analyzed without formal multiplicity adjustment. For the 1 min test, there was no statistically conclusive evidence of a between-group difference. Registration: The trial was retrospectively registered with the Chinese Clinical Trial Registry (ChiCTR2500111377), and the study materials were subsequently registered on the Open Science Framework (OSF; DOI: 10.17605/OSF.IO/VY6TS).

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030309

Authors: Robert Olivar Eleftherios Kellis

Background and Objectives: Achilles tendon rupture (ATR) incidence has increased across sport populations, and, given its impact on elite performance, the purpose of this systematic review was to synthesize the available video analysis evidence describing the biomechanics of ATR in sport. Methods: Four databases were searched to June 2026 for video analysis studies reporting the mechanics of ATR in athletes. Eleven studies (2019–2026) reporting overlapping samples of ATR events in professional basketball, soccer, and American football were included and synthesized at the study level to avoid double counting. Study quality was appraised using the QA-SIVAS scale. Results: Non-contact mechanisms predominated in all studies reporting injury dynamics (64–100%). Acceleration from a stationary or near-stationary position was the most common movement context, with the “false step” frequently described as a recurrent initiating action rather than a singular cause. Ankle dorsiflexion at the injury frame was present across all studies (25.3–47.9°). A recurrent injury-frame configuration was observed, comprising trunk flexion, hip extension, knee extension or early flexion, ankle dorsiflexion, and a flat foot, reached through a progression from initial contact. Conclusions: ATR was predominantly a non-contact injury, most often during acceleration from a near-stationary position, reaching a broadly convergent injury-frame configuration. A rearward preparatory step recurred across studies and movement categories, but inconsistent definitions and incomplete reporting mean its overall frequency cannot be established. It remains a candidate movement feature for controlled biomechanical investigation, and future work should compare successful and injurious steps within athletes.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030308

Authors: Hiroaki Kimura Ryoya Asaka Tadashi Kobayashi Hideaki Obata

Background: Thumb pain frequently arises from multiple conditions—de Quervain’s tenosynovitis, carpometacarpal (CMC) osteoarthritis, carpal tunnel syndrome, intersection syndrome, and myofascial pain syndrome—that often coexist yet are traditionally managed as separate entities. Fascial abnormalities, including hyaluronic acid-related densification and impaired interlayer gliding, have been proposed to constitute a shared pathological substrate underlying these conditions. Ultrasound-guided fascia hydrorelease (US-FHR) targeting fascial pathology has been used clinically for thumb–wrist pain; however, the anatomical targets and treatment regions have not been systematically described. Aim: This article presents a fifteen-point US-FHR clinical protocol for five converging thumb pain conditions, based on shared fascial abnormalities—densification and impaired interlayer gliding—that these conditions may have in common. It further provides a shared practical framework for pain physicians, orthopedic specialists, hand therapists, and acupuncturists. Methods: The protocol was organized based on a focused literature review on fascial biology, thumb–wrist anatomy, and the five converging conditions, combined with long-term clinical experience at Kimura Pain Clinic. For each POINT, the anatomical rationale, associated pain pattern, procedural concept, and major safety considerations were summarized. A four-direction screening test (thumb flexion, extension, abduction, and adduction) assessed in three modes (active contraction, resistance loading, and passive stretch), combined with nine established clinical tests, was integrated to identify the affected fascial structures. A diagnostic ultrasound finding characterized by multi-layered hyperechoic bands with reduced interlayer gliding—the sonographic appearance termed “stacking fascia” (a hyperechoic, stripe-shaped lesion), a previously described morphological sign that may reflect fascial densification—is described. Results: The protocol comprises 15 POINTs distributed across two approaches: nine POINTs via a dorsal approach and six POINTs via a palmar approach. The dorsal approach (9 POINTs) covers the first and third extensor compartments, their intersections (1st–2nd and 2nd–3rd), the two radial-artery crossing points (Points 5 and 6, where the radial artery passes deep to the first-compartment and EPL/ECRB–ECRL tendons, respectively), Gokoku (Hegu), the adductor pollicis, and the deep palmar arch. The palmar approach (6 POINTs) covers the thenar muscles, transverse carpal ligament, paraneural sheath and interfascicular epineurium of the median nerve, the median-nerve/FPL/FCR interface, the median nerve within the carpal tunnel, and the deeper palmar ligamentous structures adjacent to the median nerve. Periarterial release around the radial artery is proposed as a hypothesis-generating approach to CMC osteoarthritis, in which fascial constriction of periarterial tissue may contribute to subchondral vascular compromise. For each POINT, the anatomical rationale, associated pain patterns, procedural concept, and safety considerations are integrated and described. Conclusions: The proposed fifteen-point protocol represents an expanded, structured, and clinical-experience-based framework for US-FHR in five converging thumb pain conditions sharing common fascial abnormalities. It may serve as a practical basis for the standardization, education, and broader dissemination of US-FHR in this population. Prospective observational studies, randomized controlled trials, and imaging validation studies are needed to evaluate its clinical effectiveness and to test the underlying mechanistic hypotheses, including potential periarterial vascular contributions to CMC osteoarthritis.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030307

Authors: Nicoletta Palmeri Agata Grazia D’Amico Daniela Maria Rasà Carla Cavallaro Giuseppe Musumeci Velia D’Agata Grazia Maugeri

The cerebellum plays a key role in regulating movement, coordination, and certain cognitive functions. Purkinje cells are the principal neurons of the cerebellum, essential for integrating information and modulating output to other parts of the central nervous system. Physical exercise is crucial for maintaining psychophysical well-being and improving quality of life. Moreover, its beneficial effects on brain health are well established. After a brief overview of cerebellar anatomy, this narrative review aims to summarize current experimental evidence on the effects of physical activity on Purkinje cells, particularly in the context of neuronal plasticity and neuroprotection. Special attention is given to structural and functional adaptations under both physiological and pathological conditions, including neurodegenerative diseases, neurodevelopmental disorders, traumatic brain injury, and aging. Overall, the available findings suggest that Purkinje cells represent a key cellular target of exercise-induced cerebellar plasticity. Physical activity may therefore contribute to preserving cerebellar function and promoting neuroprotection through mechanisms involving structural remodeling and synaptic adaptation of Purkinje cells.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030306

Authors: Lukas Herzig Jörg Stöckert Matthias Lochmann Michael C. Rumpf

Objectives: Sided games are commonly used to condition players for the demands of official games (OGs). Therefore, this study aimed to evaluate if different sided games match position-specific locomotor and mechanical OG demands of professional football players. Methods: Twenty-one male professional football players from a second team of a professional football club were monitored during the second half of the 2024/25 season. External load was assessed during OGs and sided games. The latter were categorized by area per player (ApP) as small- (SSG, ApP < 100 m2), medium- (MSG, ApP 100–200 m2) and large-sided games (LSG, ApP > 200 m2). External load was analyzed for total distance (TD), high-speed running (HSR), sprint distance (SPD), and the number of accelerations (ACC) and decelerations (DEC). Players were grouped by position: center backs (CBs), full backs (FBs), central midfielders (CMs), wide midfielders (WMs), and strikers (STs). Results: Across all playing positions (CB, FB, CM, WM, ST), SSGs, MSGs and LSGs elicited significantly higher TD than the OG, except for CM, where no significant differences were observed during SSGs and LSGs. All positions displayed similar HSR during LSGs than OG demands, and some positions also during MSGs (CB, CM, FB) and SSGs (CB). SPD was similar across all positions only during LSGs. ACC and DEC were significantly higher for all positions in SSGs and MSGs than OGs and similar in LSGs. Conclusions: Position-specific OG demands were not statistically from different sided-game formats. ACC, DEC and TD in LSGs met OG demands; however, smaller formats (SSGs, MSGs) overload those variables. In contrast, HSR and SPR load in SSGs and MSGs did not meet OG demands for most positions. For that, coaches should use LSGs, knowing that TD may be overloaded, or supplement SSGs/MSGs with running-based drills for more accurate programming.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030305

Authors: Srdjan Markovic Tamara Stojmenovic Dragan Atanasov Dragutin Stojmenovic Milos Markovic Marina Ostojic Ivana Nedeljkovic

Background: SARS-CoV-2 infection may impair functional capacity in athletes, while prior vaccination status may be associated with post-infection functional status. However, evidence comparing objective post-infection exercise responses according to vaccination status in elite athletes remains limited. Methods: This study included a total of 220 male athletes with PCR-confirmed SARS-CoV-2 infections: 101 unvaccinated and 119 vaccinated with two doses prior to infection. Cardiopulmonary exercise testing (CPET) was performed 14 ± 1 days after confirmation of SARS-CoV-2 infection and before the athletes returned to full training. A two-way ANOVA was conducted for each CPET variable, using vaccination status and sport as fixed factors. Results: After accounting for the type of sport, vaccinated athletes showed significantly higher VO2max, VO2 at VT1, oxygen pulse, heart rate at VT1, and heart rate at VT2, as well as lower VE/VCO2 values. No significant differences were found for VEmax, HRmax, or heart rate during recovery. The interaction between vaccination status and sport was not significant for the main CPET outcomes, indicating a similar pattern in both sports. Conclusions: These findings suggest that prior vaccination is associated with a more favorable early post-infection physiological profile in professional team-sport players.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030304

Authors: Michael R. Esco

Heart rate variability (HRV) monitoring is commonly used in sport and exercise science to assess recovery, training adaptation, and performance readiness. However, the routine reporting of numerous HRV metrics with substantial conceptual and physiological overlap has created inconsistency regarding which indices should be prioritized for applied monitoring. This narrative review synthesizes the contemporary literature to provide practical recommendations regarding HRV metric selection in applied monitoring, with particular emphasis on whether the root mean square of successive differences between adjacent normal-to-normal intervals (RMSSD) may serve as the primary metric for routine HRV monitoring in many healthy sport and exercise populations. RMSSD demonstrates several characteristics favorable for applied monitoring, including strong physiological relevance, favorable reliability, compatibility with ultra-short recording durations, relative robustness during spontaneous breathing, computational simplicity, and suitability for longitudinal monitoring frameworks. Although additional HRV metrics remain valuable for addressing specific physiological, mechanistic, or research questions, the current evidence supports RMSSD as the primary metric for routine HRV monitoring in many sport and exercise settings.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030303

Authors: Kristian Plazibat

Background: Motor competence is an important basis for early childhood motor development and for the acquisition of new motor skills. Previous work from this research perspective showed that structured kindergarten kinesiology programs and overall BOT-2 motor proficiency are associated with phase-based motor learning outcomes. However, it remains unclear whether individual motor competence components are related differently to distinct phases of early motor learning. The aim of this study was to examine associations between selected BOT-2 motor competence components and phase-based motor learning outcomes in preschool children. Methods: A total of 161 preschool children participated in the study. Selected BOT-2 components were used to describe baseline motor competence. Motor learning was assessed using a standardized 7-week protocol involving previously unfamiliar kinesiology tasks and was operationalized through time to initial acquisition (F1), time to early refinement (F2), and final performance quality (K). Correlation analyses and hierarchical regression models were used, controlling for age, sex, and previous participation experience. Results: Motor competence components were positively interrelated and were significantly associated with learning outcomes. Higher baseline motor competence was generally associated with shorter F1 and F2 times and higher K scores. Participation experience showed the largest and most consistent associations across outcomes. Fine motor precision was independently associated with F1 and F2, while running speed and agility was retained as a predictor of F2. Conclusions: The findings indicate that previous structured movement experience and selected motor competence components are associated with phase-based motor learning outcomes in preschool children. These results should be interpreted as associative rather than causal and support the use of assessment-informed approaches in early childhood kinesiology programs.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030302

Authors: Norbert Farago David Horvath Bence Kopper Adam Hegedus

Objectives: External load demands (ELD) for junior basketball players have primarily been investigated in senior championships, although the competition level influences the players’ performance. The purpose of this study was to determine the between-quarter and between-position differences for U19 basketball players in their age-related championship throughout a whole competitive season. Methods: Data were collected from fifteen Hungarian U19 basketball players across eight home games via the WIMU PROTM local positioning system (Hudl, Nebraska, United States of America). Linear mixed models were used to evaluate omnibus main effects and position × quarter interactions for high-intensity accelerations (HIA), decelerations (HID), Player Load (PL), and vertical jumps (JUM), using Bonferroni adjustments and exploratory simple comparisons (p < 0.05). Moreover, model-based mean differences (MBMM) were also calculated with 95% confidence intervals (CI). Results: Significant game quarter omnibus main effect (F = 2.836, p = 0.043) and a borderline position × quarter interaction (F = 2.184, p = 0.050) were found in the JUM metric, with exploratory analyses revealing significant differences for centers between the second and third quarters and between the third and fourth quarters (p = 0.004, Mean Difference = −0.196, 95% CI = −0.345 to −0.046; p = 0.003, Mean Difference = 0.194, 95% CI = 0.049 to 0.338, respectively). A significant positional omnibus main effect (F = 4.917, p = 0.025) and a non-significant position × quarter interaction (F = 0.570, p = 0.753) was found for HID, with a significant difference between guards and forwards in the second quarter (p = 0.036, Mean Difference = 0.389, 95% CI = 0.019 to 0.742). PL and HIA did not show any significant differences. Conclusions: It is concluded that for the investigated sample, certain positional external load demands fluctuate between-quarter and between-position indicating that specific drills should be designed to maximize players’ performance and minimize their risk of injury. However, our results cannot be generalized due to the specificity of our dataset.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030301

Authors: Erick Barbalho Lage Naiara Ribeiro Almeida Sebastian Sepúlveda González Felipe Inostroza-Rios José Raimundo Fernandes Michele Andrade de Brito Diego Valenzuela Pérez Dany Alexis Sobarzo Soto Esteban Aedo-Muñoz Felipe J. Aidar Ciro José Brito

Objective: To investigate the effects of short-term ginger supplementation on physical performance, perceived exertion, and neuromuscular fatigue in CrossFit® practitioners. Methods: Thirty-two CrossFit® practitioners were randomly assigned to a Ginger group (n = 17) or a Placebo group (n = 15) in a randomized, double-blind, placebo-controlled trial. Participants consumed 2 g·day−1 of ginger or placebo for 9 days. Performance was assessed using a 10 min As Many Repetitions As Possible (AMRAP) test. Ratings of perceived exertion (RPE) and countermovement jump (CMJ) variables were evaluated before and after exercise. Results: Ginger supplementation significantly improved AMRAP performance compared with placebo (241.6 ± 18.2 vs. 225.9 ± 17.5 repetitions; F1,29 = 5.95, p = 0.021, ηp2 = 0.17). Participants in the Ginger group also reported lower RPE values (F1,29 = 24.11, p ≤ 0.001, ηp2 = 0.45). Regarding neuromuscular fatigue, ginger attenuated the decline in CMJ peak force following exercise (F1,29 = 6.62, p = 0.015, ηp2 = 0.18). No significant between-group differences were found for peak power and center of mass displacement. Conclusions: Short-term ginger supplementation improved AMRAP performance, reduced perceived exertion, and attenuated the decline in peak force following exercise in CrossFit® practitioners. These findings suggest that ginger supplementation may have potential as a natural ergogenic strategy for high-intensity functional exercise; however, further studies with larger samples are needed to confirm these effects.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030300

Authors: Artur Avelino Birk Preissler Filipe Manuel Clemente Júlio Brugnara Mello Ana Filipa Silva Rui Miguel Silva Pedro Schons

Background: Pre-season physical monitoring may help coaches understand short-term changes in youth soccer players and examine whether physical indicators are associated with early squad inclusion. This study aimed to analyze changes in physical performance during the pre-season period and to examine whether pre- and post-assessment physical performance differed between squad-included and non-included under-15 male soccer players in the first five official matches of the main competition. Methods: Thirty-seven male outfield players were assessed using the Squat Jump (SJ), Countermovement Jump (CMJ), 20 m linear sprint (Sprint-20 m), 20 m change-in-direction test (COD-20m), and Yo-Yo Intermittent Recovery Test Level 1 (Yo-Yo IRL1). Squad-included players were those listed in at least one of the first five official match reports, whereas non-included players were not listed in these reports but remained part of the broader under-15 program. Results: Significant increases were observed in SJ (+1.44 cm, p = 0.007), CMJ (+1.36 cm, p = 0.006), and COD-20m (+0.38 km·h−1, p = 0.002), whereas Sprint-20 m and Yo-Yo IRL1 did not change significantly. Fourteen players were squad-included and 23 were non-included. Squad-included players presented higher pre-assessment values for SJ, CMJ, COD-20m, and the exploratory composite physical score, and higher post-assessment values for SJ, CMJ, Sprint-20 m, COD-20m, and the exploratory composite physical score. The largest between-group difference was observed for post-assessment COD-20m (14.19 ± 0.49 vs. 13.40 ± 0.74 km·h−1, p < 0.001, d = 1.25). Conclusions: Early squad inclusion was associated with higher absolute physical performance, particularly post-assessment COD-20m, whereas the magnitude of pre-to-post changes was not clearly associated with squad inclusion.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030299

Authors: Jorge Alarcón-Jimenez Alberto Pardo-Ibáñez Nieves de Bernardo Laura García-Martínez Javier Gámez-Payá Javier Bonastre-Férez Benjamín Cuenca José Miguel Soriano Carlos Villarón-Casales

Background: Sports training induces functional and structural adaptations that may influence body composition, particularly during adolescence when growth and maturation are still occurring. Although anthropometric characteristics have been extensively studied within individual sports, comparative analyses among different sport categories remain limited. The aim of this study was to compare body composition characteristics among athletes participating in individual, team, and combat sports within a Spanish Sports Technification Program. Methods: A total of 118 young athletes (62 males and 56 females) from the Valencian Sports Technification Centre participated in this cross-sectional study. Participants were classified into three sport categories: individual sports (athletics, swimming, and triathlon), team sports (handball and volleyball), and combat sports (karate and taekwondo). Anthropometric assessment was performed according to the International Society for the Advancement of Kinanthropometry (ISAK) protocol. Body composition variables, including fat mass, muscle mass, and bone mass, were estimated using established anthropometric equations. Statistical analyses were performed using non-parametric tests, with significance set at p < 0.05. Results: After adjustment for multiple comparisons, significant differences remained between sport categories for several body composition indicators. Athletes from the individual sport group showed a higher muscle mass percentage and lower body fat percentages estimated using the Withers, Faulkner, and Carter equations than those from the team sport group. Similarly, estimated body fat percentages were lower in the individual sport group than in the combat sport group across all three equations. Team sport athletes presented higher absolute fat and muscle mass than combat sport athletes. However, some differences identified in the initial analyses, including fat mass and bone mass percentage between the individual and team sport groups and muscle mass percentage between the team and combat sport groups, did not remain statistically significant after adjustment for multiple comparisons. Conclusions: Body composition characteristics differed among the groups of young athletes participating in the specific individual, team, and combat sports included in this study. Within this cohort, athletes from the individual sport group generally exhibited lower body fat levels than those from the team and combat sport groups, whereas differences were also observed in other anthropometric characteristics. These findings should be interpreted within the context of the specific sports included and should not be generalized to individual, team, or combat sports as a whole. The findings may assist coaches, sports scientists, and health professionals in the monitoring and development of young athletes participating in similar sports and development programs.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030298

Authors: Rafael Gómez-García María de los Ángeles Cardero-Durán Luis Espejo-Antúnez Carlos Fernández-Morales

Background: Low-load resistance exercise with blood flow restriction (BFR) may increase neuromuscular stimulation while reducing external load. This pilot study examined the acute effects of unilateral knee extension at 20% one-repetition maximum (1RM) with BFR at 80% estimated arterial occlusion pressure (AOP), compared with the same protocol without BFR, on vastus lateralis surface electromyographic (sEMG) activity in healthy young adults. Methods: Twenty participants were randomized to receive BFR on either the dominant (n = 10) or non-dominant limb (n = 10); the contralateral limb completed the non-BFR condition. Both conditions were performed in randomized order during one session, separated by 10 min. Each limb completed 75 repetitions (30-15-15-15) at 20% of its limb-specific 1RM. The prespecified primary outcome was normalized RMS amplitude across 12 protocol windows, analyzed using a linear mixed model. Results: Normalized RMS amplitude was higher under BFR (between-condition difference, 21.12%MVIC; 95% CI, 14.54 to 27.71; p < 0.001). Exploratory analyses showed higher global mean and peak RMS under BFR, whereas within-protocol RMS change and temporal slope did not differ. The post-exercise percentage reduction in MVIC-derived RMS amplitude was smaller under BFR (−0.6 ± 14.1% vs. −15.4 ± 12.3%; p = 0.002). Significant secondary findings remained significant after Holm adjustment. No adverse events were spontaneously reported or observed immediately. Conclusions: Under this acute laboratory protocol, individualized BFR was associated with higher vastus lateralis sEMG amplitude than unrestricted exercise. MVIC-derived findings were exploratory and should not be interpreted as evidence of preserved strength or reduced neuromuscular fatigue. Larger studies, including clinical populations, are required.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030297

Authors: João N. A. Dias Daniel A. Marinho Luís B. Faíl Konstantinos Papadimitriou Henrique P. Neiva

Objectives: This study aimed to examine the effects of three different warm-up protocols on performance, physiological, and perceptual responses in high-level water polo players. Methods: Ten international-level athletes (Tier 4; mean ± SD: age 22.4 ± 3.53 years; height 1.78 ± 0.06 m; body mass 75.83 ± 6.44 kg) completed three experimental conditions in a randomized, counterbalanced design: dryland, in-water, and combined warm-up. Following each warm-up condition, participants performed the Water Polo Intermittent Shuttle Test (WIST), while performance (distance covered and average speed), blood lactate concentration ([La−]), heart rate (HR), tympanic temperature, and rating of perceived exertion (RPE) were assessed. Statistical significance was set at p ≤ 0.05. Results: Players covered greater distances following the in-water (331.5 ± 151.24 m) and combined (358.5 ± 134.06 m) warm-ups compared to dryland (226.5 ± 129.51 m; p < 0.01; ES = 2.00 and 1.53, respectively), with no significant differences between in-water and combined conditions (p = 0.381; ES = 0.29). Physiological responses following the WIST were largely similar between conditions, although [La−] was higher in the dryland condition (12.46 ± 4.46 mmol·L−1) compared to the combined condition at 10 min post-exercise (8.66 ± 2.47 mmol·L−1; p = 0.03; ES = 0.80). No differences were found for HR, tympanic temperature, or RPE. Conclusions: These findings suggest that warm-up protocols including an in-water component are more effective than dryland-only routines for optimizing intermittent performance in water polo players. However, combining dryland and in-water exercises does not appear to provide additional benefits compared to in-water warm-up alone.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030296

Authors: João Nuno Ribeiro Farzad Yousefian Raul Filipe Bartolomeu Faber Martins Konstantinos Spyrou Bruno Travassos Carolina Vila-Chã Pedro Tiago Esteves

Background: Futsal is a high-intensity, intermittent team sport, yet laboratory protocols that reproduce its substitution-based running demands remain scarce. This study examined the physiological, neuromuscular, and perceptual responses to the Futsal Intermittent Treadmill Protocol (FITP), a laboratory-based protocol designed to replicate the intermittent high-intensity running demands of futsal. Methods: Ten male, national-level (Tier 3) futsal players completed four bouts of intermittent running (6–20 km·h−1) reflecting typical substitution patterns. Measurements included oxygen consumption (VO2), heart rate (HR), blood lactate concentration ([BLa−]), rating of perceived exertion (RPE), total quality recovery (TQR), and countermovement jump (CMJ) performance. Responses were analyzed using one-way repeated-measures ANOVA. Results: HR and %HRmax increased significantly across bouts (p < 0.001; η2p = 0.84 for both), reaching values typical of competitive matches. Relative VO2 and %VO2max remained stable, while RPE increased and TQR decreased progressively (p < 0.001; η2p = 0.59–0.62). Blood lactate levels and the CMJ mechanical variables showed no significant changes, indicating no systematic neuromuscular fatigue pattern. Conclusions: The FITP induces substantial cardiovascular and perceptual strain that is physiologically comparable to high-intensity futsal, while metabolic and neuromuscular responses remain stable. The protocol may provide a controlled, repeatable method for assessing intermittent running tolerance; however, optimizing its role in physical evaluation, top-up conditioning, and return-to-play monitoring will benefit from future research confirming its ongoing consistency and field application.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030295

Authors: Nicola Mancini Rita Polito Giovanni Messina Marcellino Monda Francesco Paolo Colecchia Vlad Teodor Grosu Simone Lombardi Antonietta Messina Siria Mancini Fiorenzo Moscatelli

Background: This study aimed to compare changes in motor coordination associated with two different motor practice models—multisport and single-sport soccer training—in children, without implying causal effects of one training context over the other. Methods: A quasi-experimental pre–post study (T0–T1) was conducted over 10 weeks in non-randomized, pre-existing groups. A total of 143 children (mean age: 6.21 ± 0.55 years; 107 males) were allocated to a Multisport Group (MG; n = 79) and a Single-sport Group (SG; n = 64). Motor coordination was assessed using the Körperkoordinationstest für Kinder (KTK), and raw scores (RAW SCORE) were used for analysis. Statistical analyses included t-tests, change-score (Δ) and effect-size analyses, and two-way repeated-measures ANOVA. Results: Both groups showed significant improvements over time (p < 0.001; d = 0.75 for MG, d = 0.77 for SG). However, the MG showed significantly greater improvements than the SG (Δ = 16.68 ± 6.14 vs. 12.28 ± 4.08; p < 0.001; d = 0.83). At T1, the SG still showed slightly higher absolute RAW SCORE values than the MG (p = 0.049; d = −0.33), although this between-group difference was markedly reduced compared to baseline (d = −0.59). The ANOVA revealed a very large effect of Time (F(1,141) = 1092.31, p < 0.001, η2p = 0.886), a small-to-medium effect of Group (F(1,141) = 7.51, p = 0.007, η2p = 0.051), and a large Time × Group interaction (F(1,141) = 24.18, p < 0.001, η2p = 0.146). A sensitivity analysis (ANCOVA) confirmed that, after adjusting for baseline scores, sex, and anthropometric variables, the Multisport group showed significantly higher adjusted T1 scores than the Single-sport group (adjusted mean difference = 3.96 points, 95% CI: 1.93–5.99), reversing the direction observed in the unadjusted T1 comparison. Given the non-randomized design and baseline group differences, findings reflect observed associations rather than causal effects. Conclusions: Both practice models were associated with improved motor coordination, with multisport participation associated with greater observed change over 10 weeks. These findings are consistent with a possible role of diversified motor experiences in coordination development, though this study cannot establish causality.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030294

Authors: Silviya P. Nikolova Altsek Naydenov

Background: Rotator cuff tendinopathy is a common musculoskeletal disorder associated with shoulder pain, functional limitations, and reduced quality of life. A wide range of non-surgical interventions have been investigated, and uncertainty remains regarding their comparative effectiveness. Objective: This study aimed to summarize recent evidence on non-surgical treatments for rotator cuff tendinopathy and evaluate their reported clinical outcomes. Methods: A structured narrative review was conducted using Google Scholar to identify studies published between 2020 and 2025 involving adult patients with rotator cuff tendinopathy. Studies investigating exercise therapy, platelet-rich plasma (PRP), extracorporeal shockwave therapy (ESWT), laser therapy, kinesiotaping, and percutaneous electrolysis were considered. Following screening and eligibility assessment, 21 studies met the inclusion criteria. Results: Exercise therapy was the most extensively investigated intervention and consistently improved pain, function, and shoulder mobility. PRP injections were associated with favorable effects on pain and functional outcomes, although treatment protocols varied substantially. Several studies reported improvements following ESWT in pain reduction and functional recovery. Evidence from a limited number of studies suggests that high-power laser therapy may improve clinical outcomes, whereas evidence supporting low-level laser therapy remained inconclusive. Kinesiotaping and percutaneous electrolysis demonstrated potential benefits, although the available evidence remains limited. Conclusions: Exercise therapy remains the cornerstone of conservative management for rotator cuff tendinopathy. Adjunctive interventions, including PRP, extracorporeal shockwave therapy, and high-power laser therapy, may provide additional benefits in appropriately selected patients. However, methodological heterogeneity and differences in treatment mechanisms limit direct comparisons between modalities.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030293

Authors: Ivan Perasović Antonela Karmen Ivišić Dario Vrdoljak Nikola Foretić Vladimir Pavlinović Ratko Perić Mia Perić Zoran Nikolovski

Background: This study investigates the psychophysiological stress profiles of professional basketball players by simultaneously analyzing two distinct neuroendocrine pathways: the sympathetic–adrenal–medullary (SAM) system, via salivary alpha-amylase (AA), and the hypothalamic–pituitary–adrenal (HPA) axis, via salivary cortisol (C). While competitive environments are known to elicit significant stress, the interaction between game-specific variables—such as playing time (PT) and tactical position—and those biomarkers remains insufficiently explored in real-time, official match settings. Methods: Twelve professional male basketball players were monitored across four official matches. Salivary samples were collected, and stress biomarkers (AA and C) were analyzed at three timepoints: pre-match, half-time, and post-match. Results: Results indicate that stress responses are non-uniform and highly context-dependent. A significant spike in AA was observed during the first match (p < 0.001; ES = 0.82; 95% CI −0.01–1.66), where concentrations rose from a pre-match mean of 247.9 ± 232.59 U/mL to a post-match peak of 674.39 ± 693.33 U/mL. Cortisol responses did not vary significantly across matches but exhibited a strong positive correlation with PT (p = 0.01; R = 0.76), identifying that C may serve as a primary marker of individual physical workload. Positional analysis revealed significant divergence in HPA activation; guards (0.55 ± 0.31 µg/dL) and centers (0.51 ± 0.22 µg/dL) exhibited higher cortisol levels compared to forwards (0.24 ± 0.18 µg/dL), reflecting the high cognitive/decision-making load of guards and the mechanical/physical contact load of centers. Conclusions: The observed differences in AA and C liberation suggest that stress responses during matches are influenced by a complex interaction of physiological and psychological stimuli characteristic of competitive basketball. Consequently, these findings indicate the importance and value of a dual-biomarker approach which might provide a framework for optimized training load management and recovery protocols in elite basketball.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030292

Authors: Fabrizio Spataro Camila Seewald Jimena Moreira Lamas Francis Holway Francesco Campa

Background: East African runners, particularly from Kenya, have long dominated long-distance running, whereas highly trained European runners represent an appropriate comparison population to investigate structural and potentially modifiable anthropometric characteristics. Objective: To compare structural and modifiable anthropometric traits between professional Kenyan and European long-distance runners and to investigate the relationship between local muscularity and skeletal robustness. Methods: A total of 52 male marathon runners (32 Kenyan and 20 European) were assessed according to the International Society for the Advancement of Kinanthropometry (ISAK) protocol. Participants were 27.2 ± 5.2 years with a BMI of 18.4 ± 1.1 kg·m−2 and a marathon time of 02:09:26 in the Kenyan group, and 30.9 ± 4.9 years, BMI 21.1 ± 2.1 kg·m−2, and marathon time of 02:18:31 in the European group. Corrected girths were calculated to explore correlations between skeletal breadths and muscularity. Results: European runners exhibited significantly greater body mass, sitting height, girths, skeletal breadths, and muscle mass compared to Kenyan runners (p < 0.05), with large to very large effect sizes. In contrast, Kenyan runners showed lower adiposity and more linear body proportions, including a lower Cormic index and higher intermembral index. Differences in segment lengths were generally limited. Principal component analysis showed clearer group separation for modifiable than structural traits. Significant positive correlations were observed between humeral breadth and corrected arm girth (r = 0.41, p = 0.002), femur breadth and corrected thigh girth (r = 0.66, p < 0.001), and bimalleolar breadth and corrected calf girth (r = 0.72, p < 0.001). Conclusions: These findings suggest that Kenyan long-distance runners exhibit a lighter and more linear anthropometric profile than their European counterparts, whereas European runners display greater skeletal robustness and musculoskeletal development. Furthermore, local muscularity may be partly associated with underlying skeletal robustness.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030291

Authors: Gerasimos V. Grivas Walaa Jumah Alkasasbeh Adam Tawfiq Amawi

Background/Objectives: Hitting the wall (HTW) is a common and performance-limiting phenomenon in marathon running, traditionally attributed to glycogen depletion and reduced carbohydrate availability. However, the persistence of late-race performance collapse despite advances in fueling strategies suggests that HTW may not be explained by a single metabolic mechanism. Instead, HTW may represent a psychophysiological performance-collapse phenomenon arising from the interaction between physiological strain, perceived exertion, pacing regulation, and the athlete’s capacity to preserve function under prolonged stress. Methods: This narrative review aimed to synthesize the physiological and psychophysiological mechanisms contributing to HTW and to propose an integrative durability-based framework for understanding late-race performance deterioration during marathon running. Results: Current evidence indicates that HTW may emerge from the cumulative interaction of metabolic stress, thermoregulatory strain, dehydration, gastrointestinal dysfunction, neuromuscular fatigue, biomechanical deterioration, perceptual responses, and pacing errors. These stressors may progressively increase perceived effort, impair pace regulation, and reduce the athlete’s capacity to preserve physiological function and sustain the intended race pace. Within this framework, durability represents the ability to resist deterioration in physiological characteristics and performance capacity during prolonged exercise and may help explain why runners with similar fitness levels experience different late-race outcomes. Conclusions: HTW should therefore not be viewed simply as running out of fuel. Rather, it may represent the manifestation of reduced durability and psychophysiological dysregulation arising from multiple interacting stressors during marathon running. Strategies aimed at improving durability through marathon-specific training, optimized fueling, gastrointestinal tolerance, thermoregulatory preparation, neuromuscular resilience, pacing regulation, perceptual awareness, and individualized monitoring may reduce susceptibility to HTW.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030290

Authors: Harieta Elkova Galina Mratskova

The aim of this article is to provide a literature review of current approaches and recommendations for medical rehabilitation in stroke patients, with the goal of achieving the best possible outcomes for their condition and improving their quality of life. Materials and Methods: A narrative review was conducted of articles published in the databases available to us (PubMed, ScienceDirect, Google Scholar, PEDro, ResearchGate) that contain information regarding therapeutic management of stroke and, in particular, interventions aimed at motor recovery and improving quality of life. Included in this literature review were: scientific articles, guidelines on stroke and motor rehabilitation, clinical studies, longitudinal clinical studies, controlled clinical studies, systematic reviews, and meta-analyses published before April 2026, covering a ten-year period. Results: Data showing a trend toward higher patient survival rates following acute stroke were identified. For this reason, existing non-pharmacological approaches to motor recovery should be optimized. The rehabilitation process must begin as early as possible. Motor recovery depends on the establishment of motor control and the neuroplastic processes occurring in brain tissue. Rehabilitation is conducted by a rehabilitation team with the patient’s active participation, while monitoring motor rehabilitation potential. Conclusions: Rehabilitation is an essential component of post-stroke treatment. When timely and adequate medical rehabilitation is provided to stroke patients, there is a significant improvement in their overall condition and motor functions, as well as in their independence, self-care, and quality of life.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030289

Authors: Vasileios Papadopoulos Vagia Tourtouri Andromachi Navrozidou Athanasios Markou Petros Siakavellas Aliki Fiska

Background: The supraclavicular foramen (SCF) is a rare anatomical variant formed when a branch of the supraclavicular nerve traverses the clavicle through a complete transclavicular canal. Published studies differ substantially in study material, denominators, and reporting of side-specific and bilateral data, so bilateral anatomy is often synthesized as if pairing were irrelevant. Objectives: This study aimed to describe SCF in a Greek osteological sample and to apply a meta-analytic framework distinguishing per-clavicle prevalence, marginal laterality, paired laterality, and separately observed bilateral prevalence. Methods: We examined 115 dry clavicles of Greek origin for SCF frequency, size, and topography. Measurements were obtained independently by four observers using stainless-steel wires and digital calipers, with inter-rater agreement assessed by intraclass correlation coefficients. A systematic review and meta-analysis were then conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. PubMed, Scopus, and SciELO were searched from inception to 11 April 2026, supplemented by Google Scholar and backward and forward citation tracking, without language restrictions. Quantitative synthesis included pooled per-clavicle prevalence, conventional marginal left-versus-right comparison, and feasibility-based paired laterality analysis under explicit dependence assumptions when bilateral information was incomplete. Observed bilateral prevalence was analyzed separately using only studies with directly reported body-level bilateral counts. Risk of bias in the included studies was assessed using the Anatomical Quality Assessment tool, while the review itself was appraised using the Critical Appraisal Tool for Anatomical Meta-Analysis. Results: Complete transclavicular canals, identified by two external openings connected by a complete transosseous passage, were present in 3/115 clavicles (2.6%), with a mean aggregate transverse wire span of 1.5 ± 0.8 mm and a mean relative acromial position of 0.44 ± 0.01. Inter-rater reliability was excellent. Pooled per-clavicle prevalence was 2.2%, with 95% confidence intervals (CIs) 1.4–3.0% and I2 = 71%. Conventional marginal laterality supported left-sided predominance, with an odds ratio of 1.76 (95% CI: 1.16–2.66; I2 = 0%), while feasibility-based paired laterality yielded a stronger effect (paired OR = 2.26, 95% CI: 1.30–3.94). The main observed bilateral-prevalence model yielded 0.95% (95% CI: 0.33–2.70%). The Doi plot and Luis Furuya-Kanamori index indicated minor asymmetry. Conclusions: Complete transclavicular canals occurred in 2.6% of the examined clavicles and occupied a reproducible mid-to-lateral position. The meta-analysis confirmed that the variant is uncommon, supported left-sided predominance, and showed that directly observed bilateral occurrence is rare. Separating clavicle-level prevalence, marginal laterality, feasibility-based paired laterality, and body-level bilateral prevalence provided a more appropriate synthesis of incompletely paired evidence.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030288

Authors: Shkurta Rrecaj Malaj Mejdi Aliu Ardiana Murtezani Tine Kovačič

Idiopathic scoliosis (IS) is a three-dimensional spinal deformity often associated with secondary postural deviations (pelvic asymmetry, altered kyphosis/lordosis, and postural imbalance), which may negatively affect psychological well-being and quality of life (QoL). Physiotherapy interventions designed specifically for scoliosis, known as Physiotherapy scoliosis-specific exercises (PSSE), have shown effectiveness in improving primary structural outcomes such as Cobb angle (CA) and angle of trunk rotation (ATR); however, their influence on secondary postural deviations is still unclear. This scoping review aimed to summarize current evidence of PSSE on secondary postural deviations in children, adolescents, and young adults with mild to moderate IS: Following PRISMA-ScR guidelines, searches were conducted in PEDro, PubMed, Scopus and Google Scholar for studies published in the last 10 years. Eligible studies were appraised using study design-specific quality assessment tools. Randomized controlled trials (RCT) were evaluated using the Physiotherapy Evidence Database Scale (PEDro), the retrospective cohort study was assessed using the Newcastle–Ottawa Scale (NOS), and the prospective observational study was evaluated using the Joanna Briggs Institute (JBI) Critical Appraisal Checklist. Outcomes included pelvic asymmetry, spinal deviations, mobility, trunk symmetry/morphology, balance, proprioception, sensorimotor control, and QoL. Six studies involving 230 participants with mild-to-moderate IS were included. PSSE was associated with improvements in CA, ATR, postural alignment, spinal mobility, and QoL. Adjunctive interventions, including manual therapy (MT), proprioceptive neuromuscular facilitation (PNF), and hippotherapy, generally produced greater improvements in postural symmetry, pelvic alignment, proprioception, and sensorimotor control than PSSE alone. PSSE appears to improve structural, postural, and functional outcomes in individuals with IS, with adjunctive interventions potentially enhancing these effects. However, current evidence is limited by heterogeneity, highlighting the need for high-quality RCTs with standardized protocols and long-term follow-up.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030287

Authors: María Merino-País Susana López-Ortiz Enzo Emanuele Camillo Imbimbo Bruno P. Imbimbo Simone Lista Alejandro Santos-Lozano

Background and Objectives: The concept of the gut–muscle–brain axis encompasses the intricate, multidirectional interactions between the gut microbiota (GM), physical exercise (PE), and the central nervous system. Within this framework, gut dysbiosis has been implicated in the pathogenesis of Alzheimer’s disease (AD). Given that cognitive functions in AD appear to benefit from PE, it is plausible to hypothesize that these improvements may be partially mediated by PE-induced alterations in GM taxonomy. Therefore, the objective of this study is to evaluate the potential effects of PE in the GM and their implications for AD. Methods: A systematic review was conducted in PubMed, Web of Science and Scopus following the PRISMA guidelines up to July 2025 for preclinical controlled trials that assessed the effects of PE on the GM of AD animal models. A random-effects model meta-analysis was performed to estimate the pooled effect of PE on GM frequency or composition. This study received no external funding. Results: Eight studies were included in the systematic review (sample size, n = 126), of which two could be meta-analyzed. We found that PE significantly reduced Actinobacteria abundance (MD = −0.005%; 95% CI, −0.008 to −0.002; p = 0.001) with no statistically significant evidence of heterogeneity (I2 = 89.60%, Q = 0.102, p = 0.950) or publication bias observed (Begg’s test, p = 0.296), but no significant effects were found for other phylums or genera. Conclusions: PE appears capable of modulating the GM of animal models with AD in a selective and heterogeneous manner. Further studies are needed to clarify the mechanisms by which this is possible and to determinate its impact on the pathogenesis of the disease.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030286

Authors: Dawid Koźlenia

Background: Exercise-specific warm-up may influence fatigue-related performance decline and the restoration of performance between repeated resistance-training sets. This study examined whether a cambered-bar warm-up, compared with a standard-bar warm-up, affected first-repetition velocity and power retention and acceleration–time characteristics. Methods: This randomized parallel-group study included twenty resistance-trained men randomly allocated to a cambered-bar condition (CAM; n = 10) or a standard-bar condition (ST; n = 10). The warm-up comprised four sets at 30%, 50%, 60%, and 70% of one-repetition estimated maximum (1RM). After 10 min, participants completed four sets of five standard-bar repetitions at 75% of 1RM, with 2 min inter-set recovery. First-repetition mean concentric velocity retention was the principal outcome. First-repetition power retention, acceleration index, range of motion (ROM), peak velocity, time to peak velocity, and inter-set velocity rebound were analyzed using linear mixed-effects models. Results: During the loading protocol, first-repetition mean concentric velocity and power retention were greater in CAM than ST by 9.82 and 11.65 percentage points, respectively (exact participant-level permutation p = 0.044 and p = 0.012, respectively). No condition × target-set interactions were observed, indicating overall between-condition differences averaged across L2–L4 rather than different set-to-set trajectories. No condition effect was observed for inter-set velocity rebound. CAM increased warm-up ROM by 6.34 cm compared with ST. No condition effects or condition × stage interactions were observed for warm-up acceleration index, peak velocity, or time to peak velocity. The acceleration index increased across loading sets independently of condition. Conclusions: A cambered-bar warm-up increased movement range and was associated with greater retention of first-repetition mean concentric velocity and power during repeated bench press sets. However, no evidence was found for a between-condition difference in immediate inter-set velocity rebound. These findings suggest that the cambered-bar warm-up condition may support the maintenance of first-repetition mechanical performance across repeated sets, although confirmation in larger randomized crossover studies is required.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030285

Authors: Lorenzo Accurso Vincent Couturier Tristan Castonguay Julie Lamoureux Geoffrey Dover

Background: Infrared thermography (IRT) offers a non-invasive means to monitor skin temperature and physiological changes during rehabilitation. However, variability in image segmentation methods limits its broader clinical use. This study assessed the inter-rater reliability of a manual thermal image segmenatation protocol using FLIR Thermal Studio Pro™ and presents a longitudinal single-case feasibility illustration evaluating the agreement between this manual method and automatic segmentation using ThermoHuman®. Methods: Two regions of interest (ROI) were analyzed throughout the study: the frontal knee and vastus medialis oblique (VMO). For the inter-rater reliability analysis, thermal images from 20 professional athletes were used. For the agreement analysis, 50 lower extremity thermal images were captured from a single athlete recovering from a meniscal repair over a four-month rehabilitation period. Intraclass correlation coefficients (ICC (2,1)) were used to assess agreement and reliability. Results: Inter-rater reliability was excellent for all frontal knee measurements (ICC (2,1) = 0.991, 0.995, and 0.964 for maximum, average, and minimum temperature, respectively) and for VMO maximum and average temperature (ICC (2,1) = 0.967 and 0.981, respectively), with VMO minimum temperature as the exception demonstrating good reliability (ICC (2,1) = 0.779). Excellent agreement was found between methods for all frontal knee (ICC (2,1) = 0.967, 0.949, and 0.985) and VMO measurements (ICC (2,1) = 0.971, 0.973, and 0.980) for maximum, average, and minimum temperature, respectively. Conclusion: Manual segmentation using FLIR Thermal Studio Pro™ provides highly reliable results across multiple subjects, supporting its use as a practical and consistent clinical tool. Furthermore, our single-case feasibility illustration suggests it provides comparable results to automatic segmentation using ThermoHuman®, supporting its potential feasibility for accessible rehabilitation monitoring in injured athletes. Further multi-subject research is warranted to confirm the broader applicability of the agreement findings.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030284

Authors: Sheila Fernández García Sara Cerrolaza-Tudanca Eva María Rodríguez-González María Soledad Amor-Salamanca Ivan Herrera-Peco Manuel Rozalén-Bustín

Background: Female rugby players are exposed to repeated contact, impact, acceleration, deceleration, and trunk-stabilization demands that may challenge lumbopelvic control and intra-abdominal pressure regulation. Rehabilitative ultrasound imaging can characterize transversus abdominis (TrA) thickness changes during standardized tasks, although these measures should not be interpreted as direct indicators of neuromuscular activation or sport-specific trunk function. This study aimed to characterize ultrasound-derived TrA thickness and thickness change in nulliparous female rugby players and to explore whether these measures, immediate visual feedback, sport-related variables, and body mass index were associated with urinary leakage. Methods: A cross-sectional observational study was conducted with 34 nulliparous female rugby players recruited from two competitive rugby clubs. Urinary leakage was assessed using the validated Spanish version of the International Consultation on Incontinence Questionnaire-Short Form (ICIQ-UI SF), with current urinary leakage defined as leakage reported within the four-week recall period. TrA thickness was measured bilaterally using rehabilitative ultrasound imaging at rest, during the abdominal drawing-in maneuver (ADIM), and during ADIM with real-time ultrasound-based visual feedback. Exploratory analyses were conducted to examine associations between current urinary leakage and ultrasound-derived TrA measures, sport-related variables, and body mass index. Results: Overall, 41.2% of participants reported having experienced urinary leakage at some point, while 20.6% reported current urinary leakage. Among participants reporting leakage type, stress urinary incontinence was the most frequent pattern, and perceived impact on daily life was low. TrA thickness increased bilaterally during ADIM compared with rest. Immediate visual feedback did not produce a statistically significant additional increase in TrA thickness. No significant associations were observed between current urinary leakage and TrA thickness measures, side-to-side differences, weekly training hours, years of rugby practice, or body mass index. Conclusions: In this exploratory sample, ultrasound-derived TrA thickness measures during controlled ADIM tasks were not significantly associated with current urinary leakage. Future studies should include larger samples, direct pelvic floor muscle assessment, respiratory monitoring, body composition measures, and dynamic rugby-specific tasks.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030283

Authors: Rijal Rijal Huei-Ming Chai Jiu-Jenq Lin Shan Fam

Objectives: This study aimed to examine the intra- and inter-rater reliabilities of panoramic ultrasonographic measurements of the pectoralis minor length (Pm_L), pectoralis minor thickness (Pm_T), and pectoralis minor cross-sectional area (Pm_CSA). Methods: Twenty young male participants aged 19–35 years were recruited for this study. All participants had asymptomatic rounded shoulder posture (RSP), with a mean acromion-to-table distance of 59.316 ± 9.631 mm. Longitudinal panoramic scans of the Pm of the dominant arm were acquired in three trials of four measurements for all participants. The first two measurements were examined by the same rater on the same day, and the third measurement was performed by a different rater. The same procedure was carried out by the first rater after 30 days for inter-day reliability. Intraclass correlation coefficients (ICCs), standard errors of measurement (SEMs), and minimal detectable changes (MDCs) were calculated to estimate the reliabilities. Results: The intra- and inter-rater reliabilities of Pm_L, Pm_T and Pm_CSA were excellent (all ICC > 0.932; all SEM < 7.4%; all MDC < 20%). Bland–Altman plots demonstrated good agreement with nearly zero mean differences between measurements. Conclusions: Using panoramic ultrasonography to measure Pm_L, Pm_T and Pm_CSA may be considered a reliable method with excellent inter-day, intra- or inter-rater reliabilities.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030282

Authors: Dimitrios Pantazis Christos Kokkotis Alexandra Avloniti Theodoros Stampoulis Panagiotis Foteinakis Panagiotis Aggelakis Dimitrios Balampanos Maria Protopapa Alexandros Dendrinos Konstantinos Margonis Nikolaos Zaras Georgios Pafis Paraskevi Malliou Maria Michalopoulou Athanasios Chatzinikolaou

Objectives: The analysis of basketball performance has increasingly incorporated advanced analytics and machine learning methods to better understand the factors that influence offensive efficiency and match dynamics. The present study aimed to identify performance profiles in basketball using unsupervised machine learning techniques and to examine the physical load and performance indicators that differentiate these profiles. Methods: Team-quarter observations from the Final 8 phase of the Greek U16 Basketball Championship were stratified into quarters with large score differences and quarters with small score differences according to the quarter-specific score differential and the sample median of 5 points. K-means clustering was applied separately to each dataset to identify latent performance patterns. Candidate solutions were evaluated using the Elbow method, Silhouette coefficient, Calinski–Harabasz Index, and Davies–Bouldin Index. Based on their combined interpretation, together with considerations of parsimony and practical interpretability, two-cluster solutions were retained for both datasets. Cluster stability was assessed using the Adjusted Rand Index (ARI), while t-distributed stochastic neighbor embedding (t-SNE) was used exclusively for visualization of the identified clusters. Results: Welch’s independent-samples t-tests with Benjamini–Hochberg false discovery rate (FDR) correction identified significant differences between clusters across several external load variables, including jump load, total distance covered, accumulated acceleration load, and distance covered in different speed zones (pFDR < 0.001). Clusters characterized by higher movement intensity also exhibited higher values for basketball performance and offensive-efficiency indicators. Although higher-performance clusters showed numerically higher winning proportions in both contexts (large score differences: 70.0% vs. 45.7%; small score differences: 56.7% vs. 40.6%), chi-square analyses indicated that cluster membership was not significantly associated with quarter outcomes. Conclusions: Overall, the findings suggest that performance profiles in basketball are primarily differentiated by external-load characteristics, particularly movement intensity, and offensive-performance indicators, highlighting the importance of integrating both physical and technical performance indicators in basketball performance analysis.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030281

Authors: Lorenzo Alirio Diaz Balzani Guglielmo Torre Erika Albo Benedetta Tirone Giovanna Stelitano Giulia De Marco Chiara Capperucci Rocco Papalia

Background: Carpal tunnel release (CTR) surgery may have an impact on the speed and accuracy of handwriting and digital typing using a computer or mobile devices. Methods: In this prospective cohort study, patients undergoing CTR surgery of the dominant hand, between 18 and 70 years of age, with frequent use of a QWERTY keyboard and smartphone were included. A baseline Visual Analog Scale (VAS) for subjective alteration of writing and Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) were collected at a maximum 3-month follow-up. Digital typing speed (word per minute, wpm) and accuracy (number of mistakes) were tested. Handwriting was assessed by means of direct supervision of one investigator. Results: Of the 30 enrolled patients, 23 (76.7%) completed the 3-month follow-up and were included in the final analysis (mean age 55 ± 12.3 years). Pre- and post-surgery improvements in keyboard typing speed (14.8 ± 6.8 wpm to 17.6 ± 5 wpm) and mobile texting speed (16.7 ± 5.9 wpm to 21.7 ± 6.5 wpm) were significantly improved over time. Accuracy improved significantly only in keyboard typing, where the mean number of errors was reduced (13.1 ± 8.2 to 9.9 ± 5.6). QuickDASH scores decreased significantly (39.1 ± 9.1 to 17 ± 6). Conclusions: CTR surgery was associated with improved typing speed and reduced the number of errors (19% and −24%, respectively) as well as texting speed (30%). This improvement may be relevant in daily and occupational activities, as reported in the previous literature.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030280

Authors: Miguel Alarcón-Rivera Joaquín Salazar-Méndez Eduardo Guzmán-Muñoz Rodrigo Ramirez-Campillo Ivan Castillo Montecinos Luis Arturo Gómez-Landero

Objective: This systematic review examined the effects of loaded plyometric-jump training (LPJT) on physical performance outcomes in soccer players. Methods: A systematic search of PubMed, Web of Science, Scopus and Embase covered all records from database inception to February 2026, with an additional update performed in March 2026. Eligible studies were randomized controlled trials comparing LPJT with unloaded plyometric-jump training (UPJT) or passive control conditions. Methodological quality was assessed using the PEDro scale, risk of bias using RoB 2, and certainty of evidence using the GRADE approach. Findings were synthesized narratively. Results: Six randomized controlled trials involving 214 soccer players met the inclusion criteria. In general, LPJT showed favorable within-group changes in selected physical performance outcomes, particularly horizontal jump performance and some strength- and power-related variables. However, comparable improvements were also observed after UPJT in several outcomes, including vertical jump performance, linear sprint performance, change-of-direction and agility performance, and soccer-specific outcomes. Five studies raised some concerns, and one study presented a high overall risk of bias. The certainty of evidence ranged from low to very low across outcomes. Conclusions: Current evidence remains highly uncertain and does not allow firm conclusions regarding the superiority of LPJT over UPJT or passive control conditions. LPJT may therefore be considered a possible alternative to UPJT rather than a demonstrably superior approach. LPJT may be associated with favorable changes in selected performance outcomes. However, these findings should be interpreted cautiously because of the small evidence base, limited sample sizes, methodological heterogeneity, residual risk of bias concerns, and low to very low certainty of evidence. Further well-designed randomized controlled trials are needed to clarify whether LPJT provides additional benefits beyond conventional unloaded plyometric training.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030279

Authors: Nourali El Husseini Cardenas Juan D. Ascuntar Viteri Juan D. Quintero Juan Santiago Ospina-Jimenez Andres F. Rodriguez-Hernandez Emmanuel Alvarez-Londoño Jorge M. Velez Jose A. Gomez Ortiz Mateo Gomez-Ramirez Andres Rojas-Jaramillo

Proprioception is traditionally defined as the perception of joint position and movement, yet contemporary evidence supports a broader view: a multimodal sensorimotor system integrating peripheral afferent input with central motor commands. Despite its recognised importance in rehabilitation and sport, conceptual and methodological inconsistencies persist regarding its definition, assessment and training, and interventions labelled proprioceptive are frequently indistinguishable from general neuromuscular or balance-based exercise. This narrative review, reported in accordance with the Scale for the Assessment of Narrative Review Articles (SANRA), critically analyses the current state of knowledge on proprioception and clarifies the concept of proprioceptive training. PubMed, Scopus, Web of Science and SPORTDiscus were searched from January 2000 to May 2025, combining “proprioception”, “kinaesthesia”, “joint position sense” and “force sense” with “definition”, “assessment”, “training” and “rehabilitation”. Sources addressing conceptual foundations, assessment instruments, interventions explicitly labelled proprioceptive, or critical reviews were eligible, with no restriction of body region; studies on balance alone without proprioceptive measurement and non-peer-reviewed material were excluded. Of 1412 records screened, 119 informed the synthesis. Proprioception comprises distinct submodalities—joint position sense, kinaesthesia and force sense—mediated by specific receptors and pathways. Current tools isolate these under artificial conditions with limited ecological validity, and most interventions labelled proprioceptive induce general motor adaptations rather than genuine sensory ones. Submodality-specific operational definitions and ecologically valid assessment tools are required.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030278

Authors: Alejandro López-Hernández José Francisco Alonso Ramos Juan Ángel Simón Piqueras Miriam De la Torre Maroto José María González Ravé

Background: This study aimed to identify the field-based technical and biomechanical variables that best discriminate and predict competitive performance in 11–12-year-old swimmers. Methods: Seventy-two federated swimmers were assessed during a controlled technical evaluation session conducted four weeks prior to the Under-13 (U–13) Regional Championship. Variables measured included 25 m freestyle time and velocity, 25 m kick time and velocity, turn time and velocity using the 5 m in–5 m out criterion, stroke count, stroke length, and swimming efficiency index. Aqua Points were obtained from official championship results held one month after testing. Swimmers were categorized into three performance groups according to Aqua Points classification: low, medium, and high competitive level. A multiple linear regression analysis was performed to identify predictors of competitive performance. Results: Significant differences were observed between competitive levels for 25 m freestyle time and velocity, kick performance, turn time and velocity, and swimming efficiency (p < 0.05), with progressive improvements as Aqua Points increased. Significant differences were also observed for stroke count and stroke length, suggesting that stroke mechanics contributed to performance differentiation within this age group. In the regression analysis, 25 m freestyle velocity and turn velocity emerged as the strongest predictors of competitive performance, while sex was a significant covariate. The final model explained a large proportion of the variance in Aqua Points (R2 = 0.846, adjusted R2 = 0.832, p < 0.001). Conclusions: Competitive level in 11–12-year-old swimmers is strongly associated with technical proficiency, particularly short-distance swimming speed and turn execution. These findings highlight the importance of technical development during formative stages and provide practical insights for coaching strategies.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030277

Authors: Gloria Amalfi Luna-Corrales Maria Camila Rangel-Piñeros Carol Cardozo-Guzmán Ingrid Tolosa-Guzman María Constanza Trillos-Chacón Martha-Rocío Torres-Narváez

Global ageing has increased the population of people aged over 60 years, especially in low- and middle-income countries. Objective: To evaluate the postural control of adults aged 50–80 years and its relationship with age. Methodology: We conducted a cross-sectional observational study in Bogotá and nearby municipalities with 211 participants aged 50 to 80 years. We used the Balance Evaluation Systems Test (BESTest) to measure balance and excluded individuals with mobility-related conditions. We used statistical tests to analyse data from the three age groups. Results: Significant differences in postural control were found between age groups; a progressive decline in balance was shown, especially in those over 70 years old. More women than men participated in the study; performance on tasks such as standing on one leg and mobility-related activities decreased with age. Conclusions: Balance performance was lower in older age groups, suggesting an age-related decline in postural control. The findings suggest that postural balance performance is lower in older age groups, especially after 70 years of age. These results support the importance of early preventive exercise programmes aimed at maintaining balance and reducing fall risk.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030276

Authors: Iván Peña-González Alba Roldán Bartolomé Leal Barquero Alejandro Caña-Pino Manuel Moya-Ramón

Background: Inter-limb asymmetry has been widely studied as a potential determinant of physical performance in able-bodied athletes; however, its functional relevance in athletes with neurological impairments such as spastic hemiparesis remains unclear. This study aimed to examine the associations between lower-limb isometric strength, inter-limb asymmetry, physical performance, and match external-load variables in elite CP football players. Methods: Eleven male football players with spastic hemiparesis from the Spanish national team competing at the 2024 IFCPF World Cup participated in this observational cross-sectional study. Maximal isometric strength of the plantar flexors, adductors, and hamstrings was assessed using a belt-stabilised dynamometer. Inter-limb asymmetry was calculated as a percentage difference between affected and non-affected limbs. Physical performance was evaluated using sprint, change-of-direction, dribbling, and intermittent endurance tests. Match external-load variables were collected during official competition using inertial measurement units. Associations were analysed using Spearman’s rank correlations, and between-group comparisons were conducted using a median split based on asymmetry magnitude. Results: Inter-limb asymmetry did not significantly differentiate physical performance outcomes across any field-based tests (p > 0.05). Associations between isometric strength or asymmetry and field-based performance were limited and did not remain statistically significant after false discovery rate correction. In contrast, plantar flexor asymmetry showed significant negative associations with mechanical work (ρ = −0.84; q = 0.010) and metabolic power (ρ = −0.83; q = 0.010), which remained robust after multiple-comparison control. Conclusions: Inter-limb strength asymmetry did not appear to be a primary determinant of field-based physical performance in CP football players with spastic hemiparesis. Most associations between strength, asymmetry, and performance should be considered exploratory. However, plantar flexor asymmetry showed a consistent association with selected mechanical and metabolic match-load variables, suggesting that neuromuscular asymmetry may influence specific aspects of match demands. Given the exploratory team-study design and limited sample size, these findings should be interpreted cautiously and require confirmation in larger cohorts.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030275

Authors: Ana Carolina Arruda Meira Brito Alan Bruno Silva Vasconcelos Laíza Ellen Santana Santos Paulo Ricardo Martins-Filho Marzo Edir Da Silva-Grigoletto

Background: Obesity is a chronic condition that compromises health and quality of life, with physical exercise representing a relevant therapeutic strategy in its management. Functional training (FT) has been adopted as a modality that integrates neuromuscular and cardiorespiratory stimuli, promoting both physical and psychosocial benefits. However, gaps remain in the literature regarding the effects of FT on body composition in individuals with excess weight. In this context, a systematic review was conducted to analyze the current state of scientific knowledge on this approach. Methods: Randomized controlled clinical trials investigating FT were selected, including interventions classified as high-intensity functional training (HIIT-F), multicomponent programs, and CrossFit-like interventions when they fulfilled the predefined FT eligibility criteria. Participants were required to be between 18 and 65 years of age, physically independent, and in generally good health. The systematic search was conducted in the PubMed/MEDLINE, Embase, Web of Science, Cochrane Library, PEDro, and LILACS databases. The risk of bias (RoB 2.0) and the certainty of the evidence (GRADE) were assessed. Results: A total of 2,972 records were identified. Seven studies met the eligibility criteria, comprising 296 participants. Two randomized controlled trials (61 participants) were eligible for meta-analysis. The pooled analysis demonstrated a significant reduction in body fat percentage (%BF) in favor of FT/HIIT-F compared with non-exercising controls (mean difference = −4.44 percentage points; 95% confidence interval −7.08 to −1.80; p = 0.001). Risk of bias assessment showed moderate methodological limitations across studies. None were classified as low risk. Three had high risk due to missing outcome data and deviations from intended interventions, whereas four showed some concerns related to allocation concealment and analysis reporting. Bias in outcome measurement was consistently low. Conclusions: Current evidence suggests that FT/HIIT-F may be associated with reductions in %BF among adults with overweight or obesity. However, these findings should be interpreted with caution because the certainty of the evidence was rated as very low according to the GRADE approach, the quantitative synthesis included only two studies, and important methodological limitations were identified. As the available data are predominantly derived from female participants, the applicability of these findings to men remains uncertain.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030274

Authors: Banu Kabak Gökhan Deliceoğlu

Objectives: The aim of this study was to investigate the association between the effect of respiratory muscle strength parameters obtained from endurance athletes and their aerobic capacity levels. Methods: A total of 70 endurance athletes (23 women and 47 men) voluntarily participated in the study. Respiratory muscle strength was measured using a digital spirometer. Maximum VO2 was evaluated using the cardiopulmonary exercise test system (Cosmed K5). Results: As a result of the study, it was determined that in female endurance athletes, Maximum Inspiratory Pressure (MIP) and Maximum Expiratory Pressure (MEP) values were related to the End-Tidal Carbon Dioxide Pressure (PETCO2) value at maximum load. In male endurance athletes, it was determined that MEP values were related to PETCO2 values at maximum load, End-Tidal Oxygen Pressure (PETO2) values at maximum load, MaxVO2 values, VO2 values at RCP, and VO2 values at Ventilatory Threshold (VT). In addition, it was determined that in male endurance athletes, the MIP value was related to the VCO2 value at Ventilatory Threshold (RCP) and the VTidal value at maximum load. The other sub-parameters of maximum oxygen consumption (VO2) examined were not found to be related to respiratory muscle strength. Conclusions: The present findings indicate that respiratory muscle strength may be associated with selected cardiopulmonary exercise variables in endurance athletes. However, because this was a cross-sectional study, no causal inference can be made. Prospective and intervention studies are required to clarify these associations.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030273

Authors: Linshu Guan Weijian Zhang Haoliang Wang Yizhe Zhang Jiachen Sun Jun Lu

The Achilles tendon, the largest and strongest tendon in the human body, exhibits dynamic adaptive changes in its structure and function through mechanobiological regulation. This review synthesizes the dual regulatory effects of mechanical loading on Achilles tendon homeostasis and pathology: Moderate mechanical stimulation activates integrin-mediated signaling pathways (including PI3K/Akt and MAPK/ERK cascades), promoting tenocyte proliferation/differentiation, collagen biosynthesis, and orderly remodeling of extracellular matrix (ECM), thereby enhancing tendon stiffness, elastic modulus, and ultimate tensile strength. Conversely, chronic overload or disuse conditions induce collagen disorganization, aberrant matrix metalloproteinase (MMP) expression, and inflammatory cascades, creating a predisposition to tendinopathy and degenerative disorders. Emerging evidence highlights the critical role of mechanotransduction in injury repair, with early-stage progressive loading regimens demonstrating enhanced healing outcomes through optimized ECM metabolism and biomechanical signal propagation. Clinically, individualized load management strategies, including blood flow restriction training and biomaterial-assisted mechanomodulation, show promise in injury prevention and rehabilitation. Future research integrating multi-omics approaches with intelligent load-monitoring technologies may clarify mechanobiological coupling mechanisms and facilitate precision interventions for Achilles tendon disorders.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030272

Authors: Ana Campião Pedro Aleixo André Oliveira Massuça João M. S. C. Abrantes Luís Miguel Massuça

Objectives: This cross-sectional study examined associations between field bioelectrical impedance analysis (BIA)-estimated body composition, handgrip strength, event-defined centre-of-pressure (CoP) variables, and short-range police precision-shooting accuracy. Methods: Fifty-seven Police Officer Training Course cadets completed body-composition assessment, handgrip testing, and five-shot Glock 19 pistol tasks at 5 and 7 m. CoP variables were extracted during an event-defined aiming phase and a fixed 1 s post-discharge phase. Results: Shooting accuracy was higher at 5 m than at 7 m (p < 0.001). Higher BIA-estimated fat mass percentage was associated with lower shooting accuracy at both distances (p < 0.050), whereas handgrip strength was not associated with accuracy. Compared with the aiming phase, the post-discharge phase was characterized by greater CoP velocity-related measures and lower CoP amplitude and displacement (p < 0.010); these phase comparisons should be interpreted with caution because of differences in phase duration. Associations between CoP variables and shooting accuracy were generally weak. Sex-adjusted exploratory fixed-entry regression models showed modest explanatory capacity after internal validation (5 m: adjusted R2 = 0.281, LOOCV_R2 = 0.240; 7 m: adjusted R2 = 0.193, LOOCV_R2 = 0.131). BIA-estimated fat mass percentage and AP peak velocity during aiming were retained across distances, but these model-based findings should be interpreted as exploratory candidate associations rather than stable predictors. Conclusions: These findings suggest that field BIA-estimated body composition and task-specific postural regulation may be related to police precision-shooting accuracy but should be interpreted as correlates rather than determinants of performance.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030271

Authors: Ilma Čaprić Ivana Bojić Miodrag Kocić Omer Špirtović Raid Mekić Adem Mavrić Luka Pezelj Igor Jelaska Mima Stanković

Objectives: High-intensity interval training (HIIT) has become an increasingly popular conditioning strategy in women’s basketball due to its effectiveness in improving physical performance. The aim of this study was to examine the effects of a six-week HIIT on combined aerobic and anaerobic capacity, running speed, agility, repeated sprint ability, and explosive power in elite female basketball players. Methods: Thirty elite female basketball players (21.81 ± 2.12 years) were randomly assigned to either a HIIT group (n = 15) or a control group (n = 15). Results: Pre- and post-intervention assessments included running speed (0–20 m); the 5–0–5, Zig-zag, and Pro-agility tests; vertical jump performance (CMJ, CMJA, and SJ); repeated sprint ability (RSA); aerobic capacity assessed by the 30–15 Intermittent Fitness Test; and VO2max. Statistically significant Group × Time interaction effects emerged for running speed (5 m, 10 m, and 20 m), aerobic capacity (30–15 IFT and VO2max), and Zig-zag agility performance (p < 0.05), indicating greater improvements in the HIIT group compared with the control group. Significant main effects of time were observed for RSA and vertical jump performance, indicating improvements in both groups; however, no significant Group × Time interactions were found. Conclusions: These findings suggest that a six-week HIIT is an effective and time-efficient conditioning strategy for enhancing aerobic capacity, sprint performance, and change-of-direction ability in elite female basketball players.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030270

Authors: Raid Mekić Stefan Đorđević Oliver Radenković Vladan Milić Ilma Čaprić Benin Murić Milovan Bratić Izet Kahrović Omer Špirtović Rifat Mujanović Elvis Mahmutović Mia Stanojević Zoran Bajin

Background: Sagittal spinal alignment is an important indicator of musculoskeletal health during childhood. Although sports gymnastics has been suggested as a potentially beneficial form of physical activity for postural development, evidence from short-term school-based interventions remains limited. Therefore, the aim of this study was to examine the effects of an additional sports gymnastics training program on sagittal spinal alignment in fifth-grade primary school students. Methods: A total of 139 fifth-grade students (11.0 ± 0.5 years) participated in this quasi-experimental longitudinal study and were allocated to an experimental group (n = 74) and a control group (n = 65). The intervention lasted six weeks and consisted of one additional sports gymnastics session per week (60 min) in addition to regular physical education classes. Sagittal spinal alignment was assessed using the Spinal Mouse device by measuring thoracic kyphosis and lumbar lordosis. Baseline-adjusted between-group differences were evaluated using analysis of covariance (ANCOVA). Results: Small descriptive reductions in thoracic kyphosis and lumbar lordosis were observed in the experimental group; however, these within-group changes did not reach statistical significance. After adjustment for baseline values, ANCOVA demonstrated a statistically significant between-group difference for thoracic kyphosis (F = 5.05, p = 0.026, partial η2 = 0.038). Nevertheless, because the adjusted mean value was lower in the control group than in the experimental group, this finding should be interpreted with caution. No significant between-group difference was observed for lumbar lordosis (F = 2.24, p = 0.137, partial η2 = 0.017). An increase in the proportion of participants classified as having physiological sagittal spinal alignment was observed in both groups, with a descriptively greater increase in the experimental group (14.9% to 45.9%) than in the control group (7.7% to 35.4%). Conclusions: The findings provide preliminary evidence that a short-term additional sports gymnastics program may be associated with changes in sagittal spinal alignment among school-aged children. However, because of the quasi-experimental design, the low intervention dose, and the short duration of the program, the results should be considered exploratory. Further randomized controlled studies with longer intervention periods are needed to clarify the effects of sports gymnastics on sagittal spinal alignment in children.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030269

Authors: Eliete M. Colaço Alana E. F. da Gama Lucien P. Gualdi Jéssica D. M. Fonseca Daniella C. Brandão Guilherme A. F. Fregonezi Armele de Fátima Dornelas de Andrade

Background: Inspiratory training after stroke has been used to improve muscle function and strength; however, its acute effects under different inspiratory loads are not well understood. Aim: To assess inspiratory muscle activation under different incremental inspiratory loads in individuals with hemiparetic stroke and healthy controls and to compare muscle activation between hemibodies and sexes in post-stroke subjects using surface electromyography. Methods: Individuals with stroke and healthy controls were recruited. An incremental inspiratory load test was performed using the Threshold® IMT device, with progressive increases of 15%, 30%, 45%, and 60% of maximal inspiratory pressure (MIP) or up to the maximal device load based. Muscle activation of the scalene, sternocleidomastoid, and lowest intercostal space was recorded bilaterally using surface electromyography. Results: The sample consisted of 32 stroke participants (11 females and 21 males) and 14 healthy controls (six females and eight males). Muscle activity was decreased in stroke subjects in comparison to healthy individuals (p < 0.05). The paretic side showed decreased muscle activity when compared to the healthy side in all muscles during different incremental loads and maximal inspiratory pressure (p < 0.05), mainly in males. Females with stroke showed decreased activity in sternocleidomastoid (15% of MIP) and scalene (15% of MIP and MIP) (p < 0.05) compared to controls. Stroke males showed decreased diaphragm activity during 60% or maximal device load of MIP compared to controls (p < 0.05). Conclusions: Incremental inspiratory loads increased muscle activity in both stroke subjects and controls of both sexes, although in different patterns. Reduced inspiratory muscle activity on the paretic side suggests an influence of stroke on muscular function and should be considered during rehabilitation.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030268

Authors: Ranko Rajović Nenad Koropanovski Filip Kukić Igor Radošević Miloš Milošević Milivoj Dopsaj

Objectives: Effective operational functioning within the tactical domain requires a high integration of physical and psychological capacities under stressful conditions. This study investigated the impact of physical exertion at varying intensities (anaerobic and aerobic running) on subsequent change-of-direction speed (CODS) performance among police students, while evaluating the role of mental toughness (MT) and biological sex. Methods: Thirty police students (36.7% female) completed running protocols at different intensities (300-yard shuttle run and 2.4 km Cooper test), immediately followed by the Illinois Agility Test (IAT) to assess CODS performance. Mental toughness was evaluated using the Mental Toughness Index (MTI). Repeated-measures ANOVA and ANCOVA were used to analyze the main and interaction effects. Results: Initial repeated-measures ANOVA revealed that increasing running intensities significantly degraded CODS performance, demonstrating large main effects for both the anaerobic (F = 56.70, p < 0.001, η2p = 0.661) and aerobic (F = 47.50, p < 0.001, η2p = 0.621) protocols. After introducing mean-centered MT as a covariate, the main effect of Running Speed remained highly significant in both the anaerobic (F = 57.52, p < 0.001, η2p = 0.673) and aerobic (F = 46.01, p < 0.001, η2p = 0.622) models, with no significant univariate interaction effects involving MT or sex on the rate of decline. Mixed ANCOVA showed a significant main effect of sex on absolute IAT times under both anaerobic and aerobic conditions, with males consistently outperforming females. No significant differences in baseline MT scores were observed between sexes (p = 0.507). Conclusions: The findings demonstrate that physical fatigue robustly impairs CODS performance at a parallel rate for both male and female police students. Mental toughness does not neutralize the physiological rate of performance decline under acute fatigue. Practical training programs should integrate physical and psychological conditioning scenarios, while workload management protocols can be uniformly applied across biological sexes.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030267

Authors: Izarbe Ríos-Asín Elena Bueno-Gracia Isabel Albarova-Corral Pilar Pardos-Aguilella Gianluca Ciuffreda Miguel Malo-Urriés

Background: Sensorimotor impairments are common following sports injuries. Electrical Threshold Testing (ETT) is a promising quantitative sensory testing (QST) tool that allows the assessment of sensory deficits, motor recruitment, and pain perception. Although various protocols have been proposed, direct comparisons between studies and protocols remain difficult due to methodological inconsistencies, particularly regarding the number of measurements used, which significantly affect reliability. The main objective was to determine the number of trials required to obtain reliable measurements of electrical sensory threshold (EST), electrical motor threshold (EMT), and electrical pain threshold (EPT) in terms of both intra- and interday reliability. Methods: In this repeated-measures study, 14 active participants underwent three electrical stimulation protocols (sensory, motor, and pain) and performed five measurements per threshold. Averages of 1 to 5 measurements were analyzed using intraclass correlation coefficients (ICCs). Results: For EST, averaging multiple trials yielded good-to-excellent intra- and interday reliability (ICCs = 0.778–0.964). For EMT, intraday reliability was excellent (ICCs > 0.928), but interday stability remained moderate depending on the performed test. For EPT, intraday reliability was good to excellent (ICCs = 0.812–0.957), whereas interday stability (ICCs > 0.782) required averaging at least three trials. Single-trial assessments provided insufficient precision across all thresholds. Conclusions: Implementing a standardized protocol of three-averaged trials, including EST, EMT and EPT, appears to be an optimal, reliable, and time-efficient balance for clinical settings. These findings may contribute to ETT standardization in active populations, enhancing clinical efficiency, and supporting its use as a reliable tool for assessing sensorimotor impairments and monitoring treatment outcomes.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030266

Authors: Heiliane de Brito Fontana Walter Herzog Felipe Neumann Heron Baptista de Oliveira Medeiros Marcio Nunes Vitor Guarda Munari Josiel Gomes Ribeiro

Resisted sidestepping is widely implemented in rehabilitation and strength training, and exercise prescription is often guided by recommendations based on surface electromyography (EMG) patterns and intuitive assumptions about how elastic-band placement and posture influence hip loading. EMG provides valuable insight into neuromuscular strategies, but it does not, by itself, specify the direction or magnitude of joint-level mechanical demand. In this opinion article, we argue that exercise prescription is strengthened when EMG findings are interpreted within a joint-kinetic framework, in which the net external joint moment, calculated via inverse dynamics, defines the mechanical demand imposed by the task. Using resisted sidestepping as the central example and drawing on previously published three-dimensional inverse-dynamics findings, we address a common misconception that placing an elastic band around the forefeet necessarily imposes an external hip moment toward medial rotation that can help target “hip lateral rotator” muscles. Available inverse-dynamics evidence indicates that, under typical execution with slight hip and knee flexion, forefoot-band sidestepping imposes a resultant external hip moment toward lateral rotation, thereby requiring a net internal muscular moment toward medial rotation to maintain alignment and perform the task. We further highlight that posture and resistance configuration modulate how demand is distributed across joint movement planes. Specifically, band placement alters the moment arms of the elastic resistance relative to different hip joint axes and therefore influences how changes in band stiffness are translated into transverse- and frontal-plane hip loading. Thus, band placement, posture, and resistance magnitude should be selected according to the intended joint-level loading objective rather than inferred from EMG patterns alone. Although illustrated with sidestepping, this reasoning is relevant to many resistance and rehabilitation exercises in which EMG-only interpretations, without consideration of external forces and joint kinetics, may lead to incomplete or incorrect inferences about joint loading and musculoskeletal function.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030265

Authors: Nardi Tetaj Andrea Segreti Michele Pelullo Camilla Rossi Alberto Spagnolo Virginia Ligorio Aurora Ferro Antonio Emanuele Lentini Teresa Trunfio Martina Ciancio Chiara Fossati Fabio Pigozzi Francesco Grigioni

Regular endurance exercise is consistently associated with lower cardiovascular mortality, a favorable cardiometabolic profile, and superior cardiorespiratory fitness. However, coronary imaging studies in master endurance athletes have raised a clinically relevant paradox: despite a low burden of conventional risk factors, some athletes—particularly older men with high lifetime exercise exposure—show a greater prevalence of coronary artery calcium and subclinical coronary plaque than sedentary or less active controls. This observation has challenged the long-standing assumption that high-volume endurance exercise is uniformly protective against coronary artery disease. A binary interpretation of this literature is inadequate. Coronary flow reserve and ischemic threshold may remain adequate in some athletes, although this concept is supported by limited functional and outcome data. Based on experimental vascular biology and indirect human evidence, repetitive high-flow states during endurance exercise generate sustained laminar shear stress, cyclic wall strain, and marked increases in coronary blood flow, thereby activating endothelial mechanotransduction pathways and influencing vascular smooth muscle cell behavior, extracellular matrix remodeling, and calcification biology. These adaptations may culminate in positive arterial remodeling, luminal enlargement, and, in some individuals, a predominantly calcified plaque phenotype. Importantly, structural remodeling does not necessarily equate to functional impairment. In selected athletes, when outward remodeling and endothelial responsiveness are preserved, coronary flow reserve and ischemic threshold may remain adequate, although this concept remains supported by limited functional and outcome data. This narrative review integrates the clinical imaging literature with current concepts in vascular mechanobiology to propose that coronary remodeling in endurance athletes exists along an adaptive–maladaptive continuum shaped by cumulative exercise load, aging, sex, conventional risk factors, and biological susceptibility. This framework may help clinicians interpret CAC/CCTA findings in athletes more appropriately and avoid equating plaque burden with equivalent functional or prognostic significance.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030264

Authors: Koichi Moriguchi Kuniaki Moridera Tomoki Noguchi Nariyuki Mura Toshiaki Sato Hiroshi Katoh

Background: This study aimed to explore the relationships among different indices and the underlying latent structure of dynamic postural control in young female volleyball players. It used factor analysis of indices from stabilogram diffusion analysis (SDA), the modified Star Excursion Balance Test (mSEBT), and the Weight-Bearing Lunge Test (WBLT) to generate hypotheses regarding the relationships among these measures. Methods: In total, 34 female middle- and high-school volleyball players participated in this study. The SDA was performed using center-of-pressure (COP) data obtained during a single-leg vertical jump landing task, and the critical point (CP) was calculated. Lower-limb reach distances in the anterior (ANT), posteromedial (PM), and posterolateral (PL) directions were measured using the modified mSEBT. In addition, hallux-to-wall distance (HWD) was measured using the WBLT. Exploratory factor analysis was conducted to examine the latent factor structure among these indices. Results: The Kaiser–Meyer–Olkin value was 0.63, and Bartlett’s test of sphericity had significant results (p < 0.001). Considering the factor retention decision and the study’s theoretical framework, a two-factor solution was adopted for factor analysis, yielding a cumulative explained variance of 79.77%. Factor 1 had high factor loadings for the ANT, PM, and PL directions. Meanwhile, factor 2 showed high factor loadings for CP and HWD. Conclusions: Factor 1 reflected the spatial dynamic balance ability associated with the mSEBT and may be related to it. Moreover, factor 2 may indicate the temporal characteristics of COP variability assessed via the SDA and based on ankle mobility-related characteristics. However, because this was an exploratory pilot study with a small sample size, the findings should be considered as preliminary hypotheses.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030263

Authors: Carolina Oliveira de Carvalho Felipe J. Aidar Vanessa Carla Monteiro Pinto Paulo Moreira Silva Dantas Gilmara Gomes de Assis Jonathas Helber Souza Santos João Pedro de Macêdo Barros Júlio César Medeiros Alves Paulo Francisco de Almeida-Neto Luis Leitão Breno Guilherme de Araújo Tinoco Cabral

Background: Paralympic powerlifting requires high upper-limb force production within a short time frame, making anaerobic power a potentially relevant physiological component associated with competitive performance. This study aimed to analyze the associations between biodynamic variables and competitive performance in Paralympic powerlifting athletes. Methods: A cross-sectional study was conducted with 13 elite Paralympic powerlifters. Body composition was assessed using DXA. Arm isometric strength was measured by the handgrip test, dynamic strength by the medicine ball throw, and anaerobic power by an upper-limb-adapted Wingate test. Competitive performance was determined based on the official ranking position in the Brazilian Paralympic Powerlifting Championship. Results: Significant correlations were observed between all anaerobic power variables and competitive performance: relative mean power (r = −0.864; p < 0.001), mean power (r = −0.804; p = 0.003), relative peak power (r = −0.766; p = 0.006), and peak power (r = −0.791; p = 0.004). Additionally, total lean mass and left-hand grip strength showed significant associations with maximum competition lift in exploratory linear regression analyses. Conclusions: Upper-limb anaerobic power showed strong associations with competitive performance indicators in Paralympic powerlifting athletes. Furthermore, lean mass and upper-limb isometric strength showed significant associations with maximum competition lift, supporting the multifactorial nature of competitive performance in Paralympic powerlifting. These findings suggest the potential relevance of integrating power-, strength-, and body composition-oriented assessments and interventions into the training process of elite Paralympic powerlifters.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030262

Authors: Elmina-Eleftheria Roditi Themistoklis Tsatalas Giorgos K. Sakkas Ioanna Giannopoulou Yiannis Koutedakis Giannis Giakas Christina Karatzaferi

Objectives: Knee proprioception is affected by many biomechanical and physiological factors. Often, during training, rehabilitation, or specific sport requirements, weight or pressure is applied to the foot. However, it is not clear if such applications affect knee proprioceptive acuity. This study examined whether the application of an external weight (3 kg) or of pressure (120 mmHg) at a level above the ankle joint would affect knee proprioception in an open kinematic chain movement in resting or fatigue conditions. Methods: Participants included active young men (n = 7) and women (n = 15), aged 21–34 years, without prior knee injury. Women were tested in their follicular phase. An isokinetic dynamometer was used to evaluate knee joint repositioning. Three knee angles were targeted (30°, 45°, 60°) before and after localized muscle fatigue. A three-way ANOVA analysis with repeated measures and one independent variable (gender) was performed. Results: Analysis showed that ankle weight application positively influenced knee joint proprioceptive acuity resulting in an overall reduction in knee joint angular error for both genders, with the “corrective” effect most evident at 45° and 60° knee joint angles (p < 0.05), whether in the rested or fatigued state. The application of pressure however improved knee proprioceptive performance in men (p < 0.05), in both the rest and fatigue states, but not in women (ns tendency). Conclusions: Application of a small weight at the ankle level significantly improved proprioceptive knee joint acuity. These findings may have wider applicability by allowing the development of specific preventive measures towards safeguarding weaker and/or less resilient players.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030261

Authors: Maria Rita dos Santos Lara Silas Nery de Oliveira Luiz Henrique Rufino Batista Silvio Assis de Oliveira-Junior Eduardo Feijó da Rocha Rodolfo André Dellagrana Mateus Rossato

Background: Echo intensity (EI) derived from ultrasound imaging is widely used to assess muscle quality and has been proposed as a potential indicator of neuromuscular performance. Recently, EI band analysis has been suggested as an alternative approach to provide additional information beyond mean EI. However, evidence linking EI bands to functional outcomes remains limited. Methods: Forty-eight male soccer players (26.2 ± 3.6 years) underwent ultrasound assessment of the vastus lateralis (VL) and rectus femoris (RF) muscles. EI was analyzed as mean values and as pixel distribution across five bands (0–50, 51–100, 101–150, 151–200, and 201–255 A.U.), with correction for subcutaneous adipose thickness. Knee extensor peak concentric torque and total work were assessed using isokinetic dynamometry at 60°/s. Generalized linear regression models were used to examine associations between EI variables and mechanical outcomes. Results: No significant differences were observed between limbs for EI mean or EI band distribution in either muscle. The 0–50 A.U. band exhibited the highest pixel percentage for both VL and RF. Mean EI of the RF was negatively associated with peak torque (β = −4.10; 95% CI: −7.35 to −0.86) and total work (β = −3.89; 95% CI: −6.34 to −1.45) of the right knee extensors. No significant associations were found for EI bands or for any EI variables of the VL muscle. In male soccer players, mean EI of the rectus femoris, but not EI band distribution, is associated with knee extensor torque and work output. Conclusions: These findings suggest that mean EI remains a more informative indicator of muscle quality related to strength performance than band-based EI analysis in this athletic population.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030260

Authors: Sofia Sacadura Ricardo Maia Ferreira Maria Paula Pacheco Rui Soles Gonçalves

Background: Rink Hockey is a high-intensity contact sport with growing participation in Portugal, yet epidemiological data on injuries among senior and under-23 practitioners remain scarce. This study aimed to retrospectively describe self-reported injury occurrence, injury characteristics, and potential associations with demographic and sport-related variables among Portuguese Rink Hockey athletes. Methods: A retrospective, cross-sectional, self-reported e-survey was conducted among federated Portuguese Rink Hockey practitioners (under-23 and senior categories) during the 2024/2025 season. The questionnaire included 53 closed-ended items on sociodemographics, sport participation, equipment, training loads, and injury history. Injury prevalence, incidence rate, mean injuries per athlete, and associations were analyzed. Results: Among 181 respondents (68.5% male; age 22.3 ± 4.3 years; experience 15.8 ± 5.0 years), 89 (49.2%) reported at least one injury (mean 2.6 ± 2.7 injuries/athlete in the total sample; 3.3 ± 3.1 per injured athlete). Estimated incidence was 3.9 ± 5.9 injuries/1000 h (total sample) and 7.9 ± 6.2/1000 h (injured athletes). The knee (19.1%) was the most common injury localization, and muscular injuries (25.8%) were the most frequent type. Most injuries occurred during matches (46.0%), with contact with another player (27.0%) during offensive transition (40.4%) in areas surrounding the goal (57.3%) being the most frequently reported circumstances. Older and female athletes reported a higher injury prevalence than younger and males counterparts (66.7% vs. 33.3% [p = 0.042; ES = 0.174] and 61.4% vs. 43.5% [p = 0.026; ES = 0.166], respectively). Injury occurrence was positively associated with age (r = 0.262–0.158, p ≤ 0.05) and playing experience (r = 0.157, p ≤ 0.05). However, greater playing experience was associated with lower odds of joint injury (11–15 years: OR = 0.116, 95% CI [0.019; 0.695], p = 0.018; 16–19 years: OR = 0.116, 95% CI [0.019; 0.695], p = 0.018; and ≥20 years: OR = 0.056, 95% CI [0.006; 0.534], p = 0.012). Conclusions: Portuguese Rink Hockey practitioners exhibit a high injury burden, predominantly affecting the knee, with muscle injuries and contact/overuse mechanisms as major contributors. Age, sex, and experience were associated with injury occurrence. These findings may support the incorporation of targeted prevention strategies into multidisciplinary support teams.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030259

Authors: Taeseok Choi Hanshin Jeong Yohan Uhm Yoonhwan Kim

Background: Non-contact anterior cruciate ligament (ACL) injury is common and disabling, often requiring reconstruction and predisposing individuals to early post-traumatic osteoarthritis, making scalable, exercise-based prevention a clinical and public health priority. Excessive peak vertical ground reaction force (vGRF) during landing is a modifiable biomechanical risk marker for ACL injury, although whether reducing it lowers injury incidence is unproven. We evaluated the effect of movement retraining on peak vGRF during landing in pivot-sport athletes and general athletic populations. Methods: MEDLINE (PubMed), Embase, and the Cochrane Central Register of Controlled Trials were searched from inception through to 25 May 2026. Two reviewers independently screened records and extracted data. Random-effects meta-analyses (DerSimonian–Laird) used Hedges’ g; risk of bias was assessed with RoB 2 and certainty with GRADE. The protocol was registered in PROSPERO (CRD42025116119). Results: Nine comparisons from eight randomised controlled trials (292 participants) were included. Movement retraining significantly reduced peak vGRF (Hedges’ g = −0.94, 95% CI −1.34 to −0.54; I2 = 63%), with larger effects in general athletic populations (g = −1.50) than in pivot-sport athletes (g = −0.66; subgroup difference p = 0.005). Knee flexion angle at initial contact showed a non-significant increasing trend (g = 0.48; p = 0.18). Certainty of evidence (GRADE) was low. Conclusions: Movement retraining was associated with a reduction in peak vGRF during landing, a surrogate biomechanical marker for ACL injury, on the basis of low-certainty evidence with substantial heterogeneity (I2 = 63%). A subgroup difference favouring general over pivot-sport athletes was observed but is exploratory, resting on only three general-athletic comparisons. Because no included trial measured injury incidence, whether these biomechanical changes reduce ACL injury is unknown, and the findings should be regarded as hypothesis-generating.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030258

Authors: Manuel Marzola Tommaso Antonio Giacon Simona Mrakic-Sposta Costantino Balestra Alessandra Vezzoli Stefano Zappalà Simona Stimolo Michele Lazzari Katia Battista Margherita Bortolato Giulia D’Amico Gerardo Bosco

Background: Intermittent Hypoxic–Hyperoxic Training (IHHT) induces physiological adaptations. While its efficacy in athletic performance remains debated, IHHT improves health markers in pathological and geriatric populations. This Exploratory Pilot Study aimed to explore the safety and feasibility of two IHHT protocols through preliminary responses. Methods: Twelve healthy volunteers completed a 4-week intervention (two sessions/week, 45 min/session) combining IHHT simultaneously during low-intensity exercise. The study compared a Training Group (TG: 30 min hypoxia, 7.5 min normoxia, 7.5 min hyperoxia) with a Conditioning Group (CG: 15 min hypoxia, 22.5 min normoxia, 7.5 min hyperoxia). Outcomes assessed included cardiorespiratory parameters, Acute Mountain Sickness symptoms, Perceived Exertion, a comprehensive biochemical panel, systemic inflammation, oxidative stress, and renal status. Results: Both protocols were well-tolerated. The TG exhibited significantly greater oxygen desaturation than the CG (p = 0.048). Moreover, the CG demonstrated a significantly attenuated increase in Interleukin-6 (p = 0.021) compared to the TG. Additionally, preliminary variations highlighted an interesting reduction in lipid parameters (TC, LDL, and Apo A1/B ratios) in both groups, although these did not reach statistical significance after FDR correction. Conclusions: While both protocols proved feasible and safe, a more balanced hyperoxic-to-hypoxic exposure (CG) showed better acute physiological tolerability, attenuating cardiovascular strain and mitigating systemic pro-inflammatory responses compared to the unbalanced exposure (TG). Finally, the preliminary variations observed in lipid parameters provide a rationale that warrants further controlled investigations.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030257

Authors: Manuel Amore Maria Francesca Piacentini Vincenzo Sorgente Francesco Sera Diego Minciacchi

Background: Biological maturation is a major determinant of physical performance in youth football, although the previous evidence suggests that training context may influence maturation–performance associations. This study investigated the association between biological maturation and physical performance in youth football players from professional and non-professional settings. Methods: A total of 302 male football players (Under-10 to Under-14) from a professional academy (n = 122) and non-professional clubs (n = 180) participated. Biological maturation was estimated using maturity offset and age at peak height velocity (aPHV). Physical performance was assessed through standing broad jump, T-test agility, and sit-and-reach tests. General Linear Models and stratified correlation analyses were used to examine the interaction between maturation, age category, and training environment. Relative age distribution was also described. Results: Professional academy players demonstrated superior explosive power, agility, and flexibility across most age categories compared with non-professional players. Significant associations between biological maturation and physical performance were observed mainly in the non-professional environment, particularly for agility and explosive power, whereas few significant relationships emerged in the professional academy. Significant interactions between training environment, age category, and maturation status were found for all performance measures, with the strongest effect observed for agility. A relative age effect emerged only in the older professional categories. Conclusions: Associations between biological maturation and physical performance differed according to training environment in youth football players. Stronger maturation–performance relationships were generally observed in non-professional settings, whereas weaker associations emerged in the professional academy. However, due to the cross-sectional design and the likely interdependence between maturation, selection, and training exposure, causal interpretations cannot be inferred.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030256

Authors: Alexis Barbry Jérémy Coquart Caroline Verhoeven Malgorzata Klass

Background: Physical Fitness (PF) is an important health marker that should be regularly monitored with simple, time-efficient test batteries such as Diagnoform® Kid. However, its validity remains insufficiently evaluated. Therefore, this cross-sectional study examined its concurrent and construct validity against a battery of established reference tests. Methods: 184 children were grouped by age (6–7, 8–9 and 10–11 years). The Diagnoform® and reference batteries assessed identical PF components using the following tests: 6-min shuttle run-walk vs. reduced Cooper for cardiorespiratory fitness, hopscotch vs. quadrant jump for agility, standing broad jump with vs. without execution instructions for power, 5-s sprint vs. 20-m sprint for speed, and simplified fingertip-to-floor vs. sit-and-reach for flexibility. Concurrent validity was examined using bivariate correlations, and construct validity through responsiveness to age and sex. Results: Corresponding tests were significantly correlated for all PF components (p < 0.001), except for agility at 10–11 years (p = 0.094). Agility showed moderate correlations in the younger groups (r = −0.45 to −0.67). Correlations were strong for cardiorespiratory fitness and flexibility (r ≥ 0.70). For power and speed, correlations ranged from moderate (power: r ≥ 0.61 at 6–7 and 8–9 years; speed: r = 0.58 at 6–7 years) to strong (power: r ≥ 0.83 at 10–11 years; speed: r ≥ 0.70 at 8–9 and 10–11 years). Age and sex influenced performances in both batteries, except for agility (no sex effect observed) and flexibility (sex effect observed in both batteries, whereas an age effect was found only for boys on the reference test). Conclusions: Despite slightly lower responsiveness of the simplified fingertip-to-floor test to age, findings support the concurrent and construct validity of the Diagnoform® Kid tests.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030255

Authors: Hyun Ju Kim Shu Ho Kang Young Joo Cha Il Bong Park

Background: Knee osteoarthritis (KOA) alters the performance of daily activities, such as stair negotiation, by compromising lateral stability and neuromuscular control. This pilot study aimed to evaluate the feasibility of a 10-week Dynamic Neuromuscular Stabilization (DNS) program and to explore its preliminary biomechanical effects during stair ascent and descent in middle-aged women with KOA. Methods: Twenty-six participants were randomly assigned to a DNS group (n = 13) or a control group (n = 13). The DNS group completed a 10-week intervention (twice weekly). Feasibility was assessed via recruitment, retention, and adherence. Primary outcomes were mediolateral (ML) center of pressure (COP) parameters, while secondary outcomes included anteroposterior (AP) COP parameters and lower limb range of motion (ROM). Effect sizes (η2p) were estimated using 3D motion analysis and force plates. Results: The intervention showed high potential feasibility, with 100% recruitment and retention rates and 98.5% compliance. No adverse events occurred. Large effect sizes were observed for reduced ML COP velocity (ascent: η2p = 0.79; descent: η2p = 0.62) and RMS (descent: η2p =0.16). Secondary outcomes, including AP COP parameters and joint ROM (increased sagittal flexion and decreased coronal instability), also demonstrated large effect sizes. Conclusions: This pilot study suggests that progressive DNS training appears to be feasible and safe for patients with KOA. The preliminary effect sizes observed in COP control and lower kinetic chain mechanics may serve as useful foundational data for designing future adequately powered clinical trials to further examine the efficacy and underlying biomechanical mechanisms of DNS training.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030254

Authors: Peter Marián Kalanin

Background: Physical activity (PA) is associated with cardiometabolic health and functional performance, yet sex-specific evidence from real-world primary care populations remains limited. Objective: This study evaluated whether associations between self-reported PA categories and LDL-C concentrations and Timed Up and Go (TUG) functional performance differed between males and females in a real-world primary care cohort. Methods: This cross-sectional observational study included 863 adult primary care patients (424 males, 439 females). PA was categorized as low, moderate, or high based on World Health Organization recommendations. LDL-C and TUG were assessed as primary outcomes. Sex-stratified analyses included one-way ANOVA with Bonferroni post hoc comparisons and multivariable linear regression adjusted for age, BMI, arterial hypertension (AH), and diabetes mellitus (DM). An interaction term (PA × sex) was included to formally test for sex modification. Results: Males and females did not differ significantly in age, BMI, LDL-C, TUG, AH prevalence, DM prevalence, or PA distribution (all p > 0.05). Higher PA categories were associated with lower LDL-C in both males (ANOVA F = 13.03, p < 0.001) and females (ANOVA F = 14.92, p < 0.001), and with better TUG performance in both males (F = 44.21, p < 0.001) and females (F = 36.09, p < 0.001). In multivariable regression, PA was the strongest independent predictor of both LDL-C (males: β = −0.301, p < 0.001; females: β = −0.323, p < 0.001) and TUG performance (males: β = −1.235, p < 0.001; females: β = −1.170, p < 0.001) in both sexes. The interaction term (PA × sex) was not statistically significant for either LDL-C (p = 0.804) or TUG (p = 0.944), indicating no significant sex modification of the PA–outcome associations. Conclusions: The associations between self-reported PA and both LDL-C concentrations and TUG functional performance were consistent across sexes in this real-world primary care cohort. These findings support the clinical relevance of routine PA assessment as a sex-independent indicator of cardiometabolic risk and functional health in primary care. Because of the cross-sectional design, causality cannot be established.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030253

Authors: Joseba Rabanales-Sotos Sonia Piñero-Sáez Ángel López-González Francisco García-Alcaraz Jesús López-Torres-Hidalgo Carmen María Guerrero-Agenjo Jaime López-Tendero Vicente Ferrer-López

Background: Performing and maintaining high-altitude cardiopulmonary resuscitation (CPR) could pose a significant physical challenge for rescuers. The objective of this study is to analyse the effects of reducing the oxygen fraction at altitudes of 3000 m and 5000 m above sea level (asl), with and without conditioning to hypoxia, on the quality of resuscitation performed in adults. Methods: An analytical before–after study in which 56 students with a Degree in Nursing between 18 and 30 years old perform 10 min of resuscitation on a mannequin at different altitudes (670, 3000 and 5000 m asl) will be carried out. Subsequently completing an intermittent hypoxia conditioning programme, the participants will perform the resuscitation manoeuvres at previously referenced altitudes. Sociodemographics, CPR quality, self-perception CPR, adequate anthropometric data, physical condition, blood tests, oxygenation in muscular tissue, biceps, brachii and erector spinae, subjective perception of effort, anxiety levels and quality of resuscitation will be measured in all participants at different altitudes. Discussion: Although CPR is a submaximal effort manoeuvre, it is subject to being performed by anyone without motor disabilities. Our study will also provide evidence as to whether this characteristic continues to hold true in a hostile environment such as medium and high altitudes. Our study aims to demonstrate that the improvement in physical performance and recovery capacity induced by intermittent hypoxia conditioning programmes increases the quality of CPR in prolonged cardiac arrests and in adverse conditions, such as at high altitudes. The proposed study will contribute as a novelty to the estimation of the influence of high altitudes and conditioning on performing basic CPR manoeuvres. If the hypothesis turns out to be true, recommendations about the practice of moderate-intensity physical exercise could be incorporated into the CPR guidelines as one of the important aspects in the training of rescuers to conduct CPR.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030252

Authors: Hayato Miyasaka Bungo Ebihara Makoto Takahashi Takashi Fukaya Koichi Iwai Shigeki Kubota Hirotaka Mutsuzaki

Background: Deep squatting is essential for daily activities and sports; however, it is often limited after ankle fracture surgery, and the contributions of posterior ankle soft tissues, including the soleus muscle (SOL), Achilles tendon (AT), flexor hallucis longus muscle (FHL), and Kager’s fat pad (KFP), to this limitation remain unclear. This study aimed to determine the relationship between posterior ankle soft tissue properties (including stiffness and echo intensity [EI]) and deep squatting ability after ankle fracture surgery. Methods: This cross-sectional study included 53 patients (49.5 ± 16.1 years, 26 men) who underwent ankle fracture surgery. We measured the shear modulus of the SOL and AT, and the EI of the FHL and Kager’s fat pad; ankle range of motion and strength were evaluated. Deep squatting ability was also assessed. Multiple regression and receiver operating characteristic (ROC) analyses were performed to identify predictors of squatting limitation and evaluate discriminative performance. Results: Participants with a deep squatting limitation showed a higher shear modulus in the SOL and AT and higher EI in the FHL compared with those without limitations. SOL and AT shear modulus and FHL EI were significant independent predictors of ankle dorsiflexion angle during deep squatting. ROC analysis showed good discriminative ability for SOL shear modulus and AT shear modulus and modest discriminative ability for FHL EI. Conclusions: Increased stiffness and EI of the SOL, AT, and FHL were associated with reduced deep squatting ability after ankle fracture surgery. Targeted assessment and interventions addressing these tissues may improve postoperative function.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030251

Authors: Francesco Liuzza Pierfrancesco Pirri Gianluca Serra Andrea Aureli Fernando De Maio Pasquale Farsetti Giuseppe Rovere

Background: Developmental dysplasia of the hip (DDH) is one of the leading causes of secondary hip osteoarthritis and frequently results in severe anatomical alterations that make total hip arthroplasty (THA) technically demanding. Restoration of hip biomechanics, limb length, and joint stability remains challenging, particularly in patients with moderate-to-severe dysplasia. Objective: To evaluate the clinical and radiographic outcomes of cementless total hip arthroplasty combined with soft-tissue balancing, with or without acetabular reconstruction using autologous femoral head graft, in patients affected by osteoarthritis secondary to DDH. Methods: A retrospective single-center case series was conducted on eight female patients (mean age 53.9 ± 14.6 years; range 33–80 years) who underwent primary cementless THA for DDH-related osteoarthritis between 2019 and 2025. Clinical outcomes were assessed using the Harris Hip Score (HHS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Short Form-36 (SF-36). Radiographic evaluation included implant positioning, osteolysis, heterotopic ossification, bone graft incorporation, and leg-length discrepancy. Data normality was assessed using the Shapiro–Wilk test. Preoperative and postoperative outcomes were compared using paired Student’s t-test and confirmed with the Wilcoxon signed-rank test. Implant survival and revision-free status were recorded throughout the follow-up period. Results: At a minimum follow-up of 12 months (range 12 months–6 years), significant improvements were observed in all clinical outcome measures. Mean HHS increased from 49.3 ± 2.5 preoperatively to 90.4 ± 2.7 postoperatively (p < 0.001), while mean WOMAC decreased from 53.5 ± 5.6 to 7.4 ± 3.3 (p < 0.001). Mean SF-36 improved from 47.2 ± 3.8 to 89.9 ± 3.2 (p < 0.001). Wilcoxon analysis confirmed the statistical significance of these findings (all p = 0.0078). Radiographic assessment demonstrated satisfactory implant positioning and stable fixation in all patients, with no evidence of osteolysis or implant loosening. Minor complications included one intraoperative periprosthetic femoral fracture treated successfully with cerclage wiring, two cases of Brooker grade I–II heterotopic ossification, and one case of minimal graft resorption without clinical consequences. No revision procedures were recorded during follow-up, and implant survival was 100%. Conclusions: Cementless THA combined with selective soft-tissue balancing provides excellent clinical, functional, and radiographic outcomes in patients with osteoarthritis secondary to DDH. This approach significantly improves hip function and quality of life while ensuring stable implant fixation, low complication rates, and excellent mid-term implant survival.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030250

Authors: Samir Krichen Chirine Aouichaoui Hamada Chaari Liwa Masmoudi Yousri Elghoul Monia Zaouali Wajdi Dardouri Hamdi Chtourou Yassine Trabelsi Mohamed Zouch

Background: Reference values may assist practitioners in interpreting anthropometric and physical performance profiles in youth handball players within comparable sporting contexts. This study aimed to establish sex- and competitive-age-specific anthropometric and physical performance reference values for Tunisian youth handball players aged 9–15 years and to examine differences by sex and competitive age category. Methods: A total of 370 competitive youth handball players participated in this cross-sectional study (182 boys and 188 girls; U11, n = 130; U13, n = 158; U15, n = 82). Participants had at least two years of structured handball training. Assessment included body size, body composition, flexibility, squat jump, countermovement jump, 3 kg medicine ball throw, horizontal jumps, and handgrip strength. Sex, competitive age category, and sex × age category effects were examined using two-way ANOVA, with Bonferroni-adjusted post-hoc comparisons applied when appropriate. Effect sizes were reported as partial eta squared. Percentile values were calculated. Significance was set at p < 0.05. Results: Boys demonstrated higher values than girls in squat jump, (ηp2 = 0.099), countermovement jump (ηp2 = 0.097), medicine ball throw (ηp2 = 0.202), and both dominant (ηp2 = 0.073) and non-dominant handgrip strength (ηp2 = 0.048, p < 0.001). Additionally, older age categories showed higher scores on all these tests (p < 0.001). Sex- and competitive-age-category-specific percentile values were established. Conclusions: The established reference values may support descriptive benchmarking and training/monitoring among comparable Tunisian youth handball players. However, these values should not be interpreted as maturity-adjusted standards or general population norms.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030249

Authors: Christos Kokkotis Ioannis Kansizoglou Dimitrios Pantazis Alexandra Avloniti Dimitrios Balampanos Panagiotis Foteinakis Theodoros Stampoulis Maria Protopapa Alexandros Dendrinos Panagiotis Aggelakis Nikolaos Zaras Paraskevi Malliou Maria Michalopoulou Antonios Gasteratos Athanasios Chatzinikolaou

Objectives: Local positioning systems (LPSs) used in indoor team sports generate a large number of external load variables, often exceeding practical monitoring capacity. The redundancy and overlap among these variables make it difficult to identify the most informative metrics for performance analysis and load management. This study aimed to reduce the dimensionality of external load variables derived from LPS data and to identify data-driven external-load observation profiles using principal component analysis and clustering techniques. Methods: A total of 188 observations from indoor team sports (basketball, handball, and futsal) were analyzed. Continuous external load variables were standardized and subjected to principal component analysis (PCA), with component retention based on a ≥90% cumulative explained variance threshold. K-means clustering was applied in both the full standardized feature space and the PCA-reduced space. The optimal number of clusters was determined using silhouette analysis and the elbow method. Agreement between clustering solutions was assessed using Adjusted Rand Index (ARI) and Normalized Mutual Information (NMI). Cluster characteristics were further examined using descriptive statistics and variable separation analysis. Results: The first two principal components explained 53.7% of the total variance, representing high-intensity external load and neuromuscular load dimensions, while 12 components were required to exceed 90% cumulative explained variance. Clustering analysis consistently identified three moderately separated clusters in both the full and PCA-reduced spaces. The PCA-based solution demonstrated improved separation (silhouette = 0.362) compared to the full-space solution (silhouette = 0.319). Agreement between clustering approaches was high (ARI = 0.981; NMI = 0.971), indicating that dimensionality reduction largely preserved the main clustering structure within the analyzed dataset. The most discriminative variables included jump load, acceleration load, metabolic power, and anaerobic activity distance. Conclusions: A large set of external load variables can be reduced into interpretable latent dimensions that support exploratory external-load profile identification. The combination of PCA and clustering provides an exploratory and structure-preserving framework for summarizing complex external-load datasets and identifying latent load dimensions. These findings may assist future monitoring strategies; however, the practical utility of the identified profiles requires prospective validation before implementation in training-load management.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030248

Authors: Danai Paleta George Gioftsos Stefanos Karanasios Panagiotis Paletas Vasiliki Sakellari

Background and Objectives: Low participation rates in exercise programs among older adults highlight the need for theory-driven, biopsychosocial interventions that enhance adherence, self-efficacy, and functional outcomes. Grounded in principles of motor learning and behavioral reinforcement within physiotherapy practice, this study aimed to examine the effect of periodic assessments combined with verbal feedback on functional and psychological outcomes in community-dwelling older adults. Methods: A pilot RCT was conducted involving 54 individuals aged ≥65 years (53 women and 1 man), recruited from senior community centers. Participants were randomly allocated to an intervention group (periodic assessment and verbal feedback; n = 27) or a control group (n = 27). Both groups participated in an identical 12-week structured exercise program, delivered twice weekly, focusing on balance, gait, and lower-limb functional training. An intention-to-treat approach was applied. Data were analyzed using Linear Mixed Models, with statistical significance set at p < 0.05. Results: Significant group × time interactions were observed in favor of the intervention group for key kinesiology-related functional outcomes, including the Short Physical Performance Battery (SPPB; p < 0.001), Timed Up and Go test (TUG; p = 0.011), and Activities-specific Balance Confidence Scale (ABC; p < 0.001). No statistically significant differences were identified between groups for the Behavioral Regulation in Exercise Questionnaire–2 (BREQ-2; p = 0.164) and the Self-Efficacy for Exercise Scale (ESE; p = 0.108), indicating that the primary psychological outcome (ESE) was not confirmed. However, both ESE and BREQ-2 demonstrated significant baseline differences favoring the intervention group, and, therefore, these findings should be interpreted with caution despite statistical adjustment. Conclusions: Periodic assessments followed by verbal feedback appear to selectively improve the functional effectiveness of structured exercise programs in older women, particularly physical performance, functional mobility, and balance confidence, with no significant differential effect on the primary psychological outcome (ESE; group × time interaction: p = 0.108). These findings support assessment-informed and feedback-driven physiotherapy strategies as a promising adjunct to exercise programs in older adults, with potential implications for optimizing functional outcomes within applied kinesiology and rehabilitation contexts.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030247

Authors: Ciro Ivan De Girolamo Allegra Fullin Ersilia Vallefuoco Annunziata Attena Angela Lucariello Pasquale Arpaia Paolo De Blasiis

Background: The Postural Control System is affected by sensory inputs in stabilizing posture. The impact of postural receptors can be quantitatively evaluated by baropodometry. The lack of a standardized testing environment can decrease the reliability of baropodometric results. Virtual reality (VR) might represent a useful standardization tool. This study aimed to investigate the effects of virtual environment on plantar pressure and postural stability parameters by using a Head-Mounted Display (HMD). Methods: 50 healthy young adults underwent a baropodometric exam in upright standing under four conditions: Open Eyes (OE), Closed Eyes (CE), open (HMD-OE) and closed eyes (HMD-CE) conditions while wearing an HMD. Results: a negligible effect of VR on intrasubject variability of plantar pressure and stabilometric parameters. Moreover, no significant differences in the latter ones were found between OE conditions without and with headset (OE vs. HMD-OE), highlighting no impact of VR; instead, a significant increase in body sway was found in the closed eyes condition compared to OE ones with and without headset (CE vs. OE, CE vs. HMD-OE), underlining the effect of visual deprivation, whereas no significant difference was observed between the HMD-CE and OE conditions and a significant decrease in HMD-CE compared to the CE condition, showing the sensory-proprioceptive effect of the HMD. Eventually, no significant differences in plantar pressure parameters were generally found in different conditions. Conclusions: These findings highlighted the specific effect of visual afferents differently from proprioceptive ones by headset use and the absence of the VR impact on postural stability, suggesting a possible role of virtual reality in standardizing instrumental postural exam.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030246

Authors: Chieh-Ying Chiang Tzu-Han Chan Yi-Cheng Wu Sung-Kai Lin

Objectives: Skeletal muscle architecture (SMA) defines the mechanical limits of force production. However, its associations with force–time strategy under externally loaded conditions have received little research attention. This exploratory study examined associations between vastus lateralis (VL) and lateral gastrocnemius (LG) architecture and force–time strategy, jump-height retention, and stretch–shortening cycle (SSC) transfer-efficiency in collegiate basketball players. Methods: Seventeen collegiate male basketball players completed B-mode ultrasonographic assessment of VL and LG architecture, including muscle thickness, pennation angle (PA), and fascicle length. Athletes performed the squat jump (SJ), loaded squat jump (LSJ), countermovement jump (CMJ), and loaded countermovement jump (LCMJ) on force platforms, with a 20 kg external load applied for loaded conditions. Loaded retention, defined as the percentage of jump height preserved under load, was proposed as a unified construct. Pearson’s correlations were calculated, with Benjamini–Hochberg false discovery rate (FDR) corrections applied within predefined functional groups and pooled across morphology-sensitive correlations. Results: LG PA showed a large negative association with LCMJ rate of force development (r = −0.68 [−0.87, −0.30]) and a large positive association with LCMJ time to peak force (r = 0.68 [0.29, 0.87]), both surviving within-group FDR correction. VL PA was associated with eccentric acceleration time and concentric time across jump conditions (r = 0.52 to 0.61), interpreted as exploratory. Transfer-efficiency indices showed no significant associations with SMA, except for the LCMJ/LSJ concentric time ratio, which showed a moderate negative association with LG PA (r = −0.49 [−0.79, −0.01]). Conclusions: Resting muscle architecture was associated with the temporal and rate characteristics of force expression under load, rather than with the gross preservation of jump height. Integrating architectural assessment with loaded force–time profiling warrants further investigation as a means of characterizing individual force-development strategies.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11030245

Authors: Dan Cristian Mănescu Cristina Filip Cristina Ionela Nae Rela Valentina Ciomag

Although athlete monitoring can quantify training exposure and athlete status with increasing detail, conversion into daily training decisions remains inconsistent. This structured narrative review synthesizes evidence on training load, neuromuscular readiness, recovery, fatigue interpretation, measurement reliability, applied decision-making, and proposes the LOAD-R framework: a systems model linking Load, Organism response, Adaptive state, Decision, and Re-evaluation. A transparent non-PRISMA strategy was used because the aim was conceptual integration and framework development rather than effect-size pooling. Evidence was organized around field-applicable monitoring domains and their decision value. LOAD-R builds on existing monitoring approaches by organizing single indicators, fixed thresholds, and dashboard alerts into an explicit interpretation-to-action sequence. It classifies athlete state into adaptive, functional-overload, underloaded, uncertain, or maladaptive zones, each linked to progress, maintain, modify, deload, or recover decisions. The framework also provides implementation levels and testable predictions. By framing monitoring as adaptive decision support rather than passive data collection, LOAD-R may improve decision consistency, reduce maladaptive training responses, and enhance the practical value of athlete monitoring in applied sport settings.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11020244

Authors: Sousana Symeonidou Afroditi Lola Georgia Stavropoulou Anastasios Dalkiranis Marios Bismpos Eleni Bassa

Background: Morphological characteristics influence physical performance in youth basketball, but their effects may differ by developmental stage. This study compared the predictive role of morphological variables on motor performance between U13 and U15 male players. Methods: Male youth basketball players (N = 89) were assigned to U13 and U15 groups. Morphological variables included height, body mass, body fat percentage, and fat-free mass (FFM). Motor tests evaluated squat jump (SJ), countermovement jump (CMJ), 10 m and 20 m sprints, T-test, Y-test and Stop-and-Go change-of-direction speed and reactive agility (RA). Pearson correlations and multiple linear regressions assessed relationships and predictive effects. Results: In U13 players, several morphological variables correlated with performance: height and FFM were positively related to jumping and sprinting, while body fat was negatively associated with most measures (p < 0.05). Regression models explained substantial variance in sprint (ranging up to AdjR2 = 0.44) and jump performance (ranging up to AdjR2 = 0.32), though individual predictors were not always significant (p > 0.05). In U15 players, fewer associations emerged as body fat remained a significant negative predictor of jumping and agility, and greater body mass was associated with improved sprint performance (p < 0.05). No significant morphological predictors were found for RA in either group (p > 0.05). Conclusions: Morphological traits exert a stronger, multifactorial influence on performance in younger athletes, whereas body composition and particularly body fat are more influential in older adolescents. These results underscore the need to consider the developmental stage when assessing and training male youth basketball players.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11020243

Authors: Milivoj Dopsaj Athanasios A. Dalamitros Klara Šiljeg Andrea Perazzetti Antonio Tessitore Alexandros Nikolopoulos

Background and Objectives: Water polo (WP) is a high-intensity, intermittent aquatic team sport that has been extensively investigated within sports science. While contemporary literature has examined the body composition and morphological characteristics of elite and international WP players, this study aimed to define the general body composition profile of world-class WP players and determine position-specific differences. Methods: The study involved 72 national team players from Serbia, Croatia, Greece, and Italy who participated in the Olympic Games, World Championships, or European Championships. Participants’ body composition was measured using the InBody 720 multichannel bioimpedance method. Ten different variables were examined to assess body structure regarding contractile and ballast components. Results: MANOVA revealed statistically significant differences in body composition across playing positions (Wilks’ lambda = 0.239, p < 0.000, η2p = 0.402). The variables that had the greatest impact on the difference were: body mass, body fat and body mass index with the 47.0, 44.4, and 43.7% of explained total variance of the impact on the differences (p = 0.000), respectively. Conclusions: world-class WP players assigned to different playing positions differ significantly in body composition. These positional profiles should be considered in talent identification, selection procedures, training, and nutritional strategies to optimize performance models, considering the future evolution of the game at the highest competitive level. Coaches could use this information to initially select players for different specific positions based on anthropometric and body composition criteria.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11020242

Authors: Diogo Tereso José M. Gamonales Víctor Hernández-Beltrán Rui Paulo

Background: Football is an intermittent sport characterized by high physical and physiological demands, which may be influenced by the competitive level. Understanding differences in match load is fundamental for optimizing training planning, fatigue management, and athlete performance and injury prevention. This study aimed to evaluate and compare external and internal load in senior football players in Portugal across five distinct competitive levels. Methods: Wimu ProTM (Hudl, Lincoln, NE, USA) and Garmin Heart Rate bands (Garmin International Inc., Olathe, KS, USA) were used to quantify and evaluate the external and internal load of the players. A total of 96 athletes were assessed, with ages ranging from 19 to 36 years (mean: 24.28 ± 4.72), who were divided into five competition levels (1st Division (n = 19), 2nd Division (n = 21), 3rd Division (n = 14), 4th Division (n = 20), and Regional Division (n = 22). Results: Significant differences were observed between competitive levels across several external load variables (p > 0.001). The 3rd Division and 4th Division showed higher values in variables associated with reactive and high-intensity actions (p < 0.001; effect size: 0.287), whereas the 2nd Division exhibited a more controlled load profile. Regarding internal load, significant differences were only observed in average heart rate during the second half (p = 0.043; effect size: 0.085), indicating distinct capacities to maintain physiological intensity under fatigue. Conclusions: It can be concluded that competitive level influences load profiles in football, although the differences do not follow a linear pattern. External and internal loads demonstrate greater discriminatory capacity between competitive levels than internal load.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11020241

Authors: Giacomo Capece Gerardo Giudice Ruggiero Giliberti Pierluigi Di Cosmo Giuseppe Pizzi Luca Lepore Rosario Junior Sagliocco Francesco Cuozzo Emidio Di Gialleonardo Michele Gison

Lateral femoral neck and peritrochanteric fractures are common and clinically challenging injuries, particularly in the elderly population, with significant implications for morbidity, mortality, and functional recovery. Traditional classification systems are widely used to guide treatment, yet their reproducibility and clinical applicability remain debated. Increasing attention has been directed toward trabecular architecture and its role in fracture behavior and reduction strategies. This review aims to summarize current evidence on classification systems, trabecular-based fracture patterns, pre-operative reduction techniques, and fixation strategies. A narrative review was conducted using PubMed/MEDLINE, Embase, and Scopus databases up to May 2026. Original studies, reviews, and biomechanical investigations focusing on proximal femur fracture classification, reliability, trabecular alignment, reduction techniques, and fixation methods were included. Data were qualitatively analyzed, with emphasis on interobserver reliability, biomechanical implications, and clinical outcomes. Conventional classification systems, including anatomical, Evans–Jensen, and AO/OTA frameworks, demonstrated variable and generally moderate reproducibility, with reported interobserver agreement ranging from approximately κ = 0.30 to 0.60. Emerging evidence highlights the importance of trabecular architecture, distinguishing intradigital fractures—confined within trabecular pathways and relatively stable—from extradigital fractures, which disrupt load-bearing structures and are associated with increased mechanical instability and higher failure rates. Biomechanical and clinical studies indicate that inadequate reduction with trabecular misalignment significantly increases the risk of varus collapse and implant cut-out. Reduction strategies tailored to fracture pattern, such as internal rotation for intradigital fractures and external or combined maneuvers for extradigital patterns, improve alignment and load transfer. In terms of fixation, dynamic hip screws remain effective in stable fractures, whereas cephalomedullary nails demonstrate superior performance in unstable patterns, with lower reoperation rates reported (approximately 5–8% vs. 10–15%). Management of lateral femoral neck and peritrochanteric fractures should extend beyond traditional classification systems to incorporate trabecular biomechanics. Restoration of trabecular alignment, alongside established parameters such as neck–shaft angle and tip–apex distance, is critical for optimizing outcomes. Further prospective studies are needed to validate trabecular-based classifications and standardize reduction strategies.

Journal of Functional Morphology and Kinesiology doi: 10.3390/jfmk11020240

Authors: Joshua J. Aube Peter J. Mendolia Kristi L. Storoschuk Ely Wyman Mason D. Peberdy John J. Wu Nia Simpson-Stairs Paul A. Swinton Brendon J. Gurd

Purpose: The current study tested the hypothesis that a bodyweight training (BWT) protocol with a higher weekly time commitment and training volume would produce greater improvements in cardiorespiratory fitness compared to lower time commitment/volume BWT protocols. Methods: Fifty-eight (n = 21 males; n = 37 females) recreationally active, healthy, young adults were randomized to either a 16 (TAB, n = 20), 27 (5BX, n = 19), or 90 min/week (AMRAP, n = 19) BWT protocol for 6 weeks. Peak work rate (WRpeak) was measured pre- and post-intervention using a cycle ergometer graded exercise test. VO2peak was estimated (eVO2peak) using a simple linear regression of WRpeak and VO2peak generated from a previous study (n = 26; 13M/13F). Results: TAB and 5BX yielded non-inferior improvements in eVO2peak. The 95% confidence intervals of the mean difference in change did not cross our non-inferiority margin of −2.6 mL/kg/min (TAB—AMRAP = 95% CI = −1.16 to 2.07; 5BX—AMRAP 95% CI = −0.29 to 2.89). Conclusions: Our results suggest that 16 and 27 min/week of minimalist BWT yields non-inferior improvements in CRF compared to 90 min/week and provides evidence supporting the efficacy of low-volume BWT protocols compared to higher volume protocols. The study was registered on Open Science Framework on 29 May 2023 (OSF registration).