Search Results (276)

Background/Objectives: Exercise-induced fatigue is a fundamental component of running performance and training, yet it is also implicated in altered movement mechanics and increased injury risk. While numerous studies have examined fatigue-related biomechanical changes during running, findings remain fragmented across biomechanical domains and fatigue modalities. The purpose of this systematic review was to synthesize contemporary evidence on the effects of fatigue on lower-limb biomechanics during running and to interpret the potential injury relevance of these adaptations. Methods: A systematic literature search was conducted in PubMed, Scopus, and Web of Science for original empirical studies published between January 2010 and December 2025. Eligible studies involved human participants performing running or running-related tasks, applied an explicit fatigue protocol, and reported quantitative lower-limb biomechanical outcomes. Study selection followed PRISMA 2020 guidelines. Data extraction included participant characteristics, fatigue protocols, biomechanical measures, instrumentation, and key findings. Methodological quality was assessed using the Cochrane Risk of Bias 2 (RoB-2) tool. Due to substantial methodological heterogeneity, findings were synthesized narratively. Results: Twenty-four studies met the inclusion criteria. Across studies, fatigue consistently altered spatiotemporal parameters, joint kinematic and kinetic variables, spring-mass behavior, impact loading, coordination variability, neuromuscular output, and inter-limb symmetry. Common adaptations included increased ground contact time, reduced ankle joint power and stiffness, increased joint range of motion, elevated impact loading, and greater movement variability. These changes reflected reduced mechanical efficiency and a redistribution of mechanical load from distal to proximal joints, particularly toward the knee and hip. Similar fatigue-related biomechanical patterns were observed in both laboratory-based and real-world endurance running conditions. Conclusions: Exercise-induced fatigue produces systematic and injury-relevant alterations in lower-limb biomechanics during running. These adaptations may preserve short-term performance but create mechanical conditions associated with increased susceptibility to overuse and non-contact injuries. Integrating fatigue-aware biomechanical assessment, neuromuscular conditioning, and individualized load management strategies may help mitigate adverse fatigue-related adaptations. Full article

Arterial stiffness encompasses the global structural and functional modifications that induce progressively increased vascular rigidity, whether associated with pathological cardiovascular or metabolic alterations or not. This narrative review highlights the comparative effects of physical exercise practices, current drug treatments, and approaches based on the use of medicinal plants on arterial stiffness, due to metabolic and/or blood pressure disorders. This review would provide up-to-date information for further experimental and clinical studies concerning the prevention/therapy of high glucose levels and vascular remodelling. Indeed, it is known that physical activities can reduce high blood glucose and blood pressure, allowing the prevention of arterial stiffness. Concerning conventional drugs, some are used to treat arterial stiffness, but their effectiveness is generally limited to treating components of the disease. Eighteen medicinal plant species, belonging to fourteen different botanical families, have potential activities against arterial stiffness in preclinical and/or clinical studies. Several plant extracts reduced the parameters implicated in vascular stiffness, such as the Pulse Wave Velocity, the Augmentation Index, and the Cardio–Ankle Vascular Index. Some plant extracts reduced arterial stiffness by primarily lowering glycemia and/or blood pressure in animal models, which has also been confirmed in humans. By reducing arterial stiffness, plant extracts or derived bioactive compounds not only improved vascular relaxation by enhancing Nitric Oxide production and/or antioxidant defences, but also inhibited inflammation-induced aortic remodelling and promoted elastin neo-synthesis. Polyphenols have often been identified as the main effective compounds involved in these beneficial effects. However, only a few studies explained the mechanisms associated. Full article

Objectives: We aimed to investigate the effects of 6 weeks of leucine supplementation on athletic performance, central fatigue, and serum metabolome in endurance athletes, and to provide valuable insights into nutritional strategies for endurance athletes. Methods: Twenty cross-country skiers were recruited and randomized into 2 groups: the placebo (PLA) group and the leucine (LEU) group. Subjects were given leucine (8.5 g) + sucrose (14 g) or only sucrose (14 g) supplements twice each day from Monday to Saturday for 6 weeks. Test parameters include body composition, aerobic capacity, isokinetic muscle strength, blood biochemistry, and targeted metabolomics. Results: After intervention, compared to the PLA group (1) the ankle muscle strength (p = 0.01), VO₂max (p = 0.01) and valine in serum (p = 0.03) were increased in the LEU group. (2) Targeted metabolomics results showed that the differential metabolites were enriched in the branched chain amino acids (BCAAs) biosynthesis and degradation. (3) The LEU group had a significant increase in α-ketoisovaleric acid (p = 0.03), which can reduce the continuous decomposition of BCAAs. Conclusions: In conclusion, a six-week intervention of leucine supplementation significantly enhanced ankle muscle strength in endurance athletes, likely through a reduction in BCAA catabolism. Additionally, this combined supplementation strategy demonstrated potential benefits in improving aerobic endurance and may contribute to the attenuation of exercise-induced central fatigue. Full article

Background/Objectives: Improper landing mechanics in Taekwondo can lead to non-contact injuries such as ankle sprains and knee ligament tears, highlighting the necessity for objective methods to evaluate landing stability and injury risk. Electromyography (EMG) enables the examination of muscle activation patterns; however, conventional analyses based on simple averages have limited predictive value. Methods: This study analyzed EMG signals recorded during single-leg landings (45 cm height) in 30 elite male Taekwondo athletes. Participants were divided into regular exercise groups (REG, n = 15) and non-exercise groups (NEG, n = 15). Signals were segmented into two phases. Eight features were extracted per muscle per phase. Classification models (Random Forest, XGBoost, Logistic Regression, Voting Classifier) were used to classify between groups, while regression models (Ridge, Random Forest, XGBoost) predicted continuous muscle activation changes as injury risk indicators. Results: The Random Forest Classifier achieved an accuracy of 0.8365 and an F1-score of 0.8547. For regression, Ridge Regression indicated high performance (R² = 0.9974, MAE = 0.2620, RMSE = 0.4284, 5-fold CV MAE: 0.2459 ± 0.0270), demonstrating strong linear correlations between EMG features and outcomes. Conclusions: The AI-enabled EMG analysis can be used as an objective measure of the study of the individual landing stability and risk of injury in Taekwondo athletes, but its clinical application has to be validated in the future by biomechanical injury indicators and prospective cohort studies. Full article

Background: Conservative treatment of chronic musculoskeletal pain includes exercise, manual therapy, medications, physical agents/modalities, and Therapeutic Patient Education (TPE). Research on TPE has predominantly focused on spinal pain, so we do not know the extent and scope of clinical research in other areas, particularly lower extremities. This review aimed to map current research on this topic. Methods: We searched PubMed, PEDro, CINAHL, PsycINFO, and Cochrane Library up to 1 April 2024. We included RCTs on adults with chronic lower limb musculoskeletal pain, written in English, French, Spanish, or Italian. Results: Fifty-two records concerning knee osteoarthritis (n.33), hip and knee osteoarthritis (n.8), hip osteoarthritis (n.3), chronic knee pain (n.3), patellofemoral pain (n.3), and gluteal tendinopathy (n.2) were included. TPE was delivered through self-management, disease-specific information, pain education, and the management of physical activity, load, diet, stress, and sleep. Interventions were both individual- and group-based; delivery methods included in-person intervention, telephone/video calls, and web tools/apps. TPE combined with exercise seemed to be more effective than exercise alone, information/little education, or usual care. The effects of TPE as a stand-alone intervention appeared uncertain. Conclusions: There is considerable variability in TPE in terms of teaching topics, providers, administration methods, and dosage of interventions. Future studies should investigate the effects of TPE in young adult populations and in ankle conditions. They should also investigate the effects of TPE on pain intensity versus pain interference with activities, by deepening TPE effects on disability and quality of life. Full article

Background: Ankle sprains affect approximately 8% of the general population, and recurrence occurs in as many as 80% of patients participating in high-risk sports. The aim of this review was to assess the impact of physiotherapy interventions on chronic ankle stability (CAI), providing evidence for the effectiveness of clinical treatment and care for patients with CAI. Methods: A systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Randomized controlled trials (RCTs) evaluating the effectiveness of physiotherapy interventions in athletes with CAI following injury were analyzed. PubMed, Embase, PEDro, and Cochrane electronic databases were searched. A modified McMaster Critical Review Form for quantitative studies was used to assess the methodological quality of the included studies, in accordance with the guidelines. Results: The literature search yielded 316 results, of which 13 articles met all required eligibility criteria and were included in the study. The RCTs included 490 athletes with CAI. Interventions included various types of exercises, including balance training (BT), plyometric training, CrossFit, and neuromuscular training. The duration of the intervention was 4–12 weeks. Both subjective and objective measures were used to assess the effectiveness of the therapy in the following seven domains: Dynamic Balance, Static Balance, Patient-Reported Outcomes, Kinematic Outcomes, Proprioception, Body-Composition, and Strength Assessment. Conclusions: The evidence supports the effectiveness of rehabilitation interventions in athletes with CAI. Further large-scale randomized controlled trials, incorporating control groups and long-term follow-up, are needed to better determine the robust impact of conservative management on improving both the physical and psychological health of patients with CAI. Full article

The purpose of this study was to determine the effects of coordination training and strength training on the lower extremity inter-segmental coordination during instep kicking for novices. Thirty-two male college students with no soccer-specific training experience participated and were randomly assigned to either a coordination training group, a strength training group, or a kicking training group. Both the coordination and strength training groups also performed the same kicking training as the kicking training group. Each participant executed exercise training three times a week for eight weeks. The instep kicking test was performed before and after the three training sessions. Two-way ANOVAs were conducted to determine the training effects on the kicking performance and the inter-segmental coordination. The maximum ball speed significantly increased for all three training groups (p < 0.001, effect size = 0.638). In contrast, improvements in kicking accuracy were specific to the coordination training group (p = 0.001, effect size = 0.326), with no significant changes observed in the strength (p = 0.052, effect size = 0.138) or kicking groups (p = 0.953, effect size < 0.001). The time spent percentage of the knee-ankle shank-phase coordination pattern in the leg-cocking phase was significantly increased (p = 0.003, effect size = 0.268), but the time spent percentage of the hip-knee thigh-phase in the back swing phase significantly decreased after the three trainings (p = 0.031, effect size = 0.150). A significant reduction in the relative activity of the tibialis anterior and gastrocnemius muscles occurred exclusively after coordination training (p = 0.024, effect size = 0.188). This study confirms that coordination training provides a unique contribution to skill acquisition in novices, specifically enhancing kicking accuracy and neuromuscular control, whereas improvements in maximal ball speed were generic to all training types. Full article

This study investigates the joint mechanical power (JMP) distribution in the half squat (HS) exercise through the Power-Based Training (PBT) framework, with the primary aim of providing preliminary methodological validation of this analytical approach and illustrating its capacity to characterize joint contributions across movement phases and load levels. Five professional weightlifters performed HS under five progressive loads (20–80% 1RM), while kinematics and kinetics were recorded with a Vicon motion capture system and force platforms. JMP at the hip, knee, and ankle was analyzed in four distinct movement phases. Results indicated that joint contributions varied with load and phase. Under light loads the knee tended to produce most power. As load increased, contributions shifted proximally: the hip increased both absorption and production, and the ankle’s relative contribution grew in the final lifting phase. The main eccentric (lowering deceleration) and concentric (lifting acceleration) phases concentrated the highest JMP values, though differences between phases diminished at higher loads, suggesting a more homogeneous effort distribution. These findings support the feasibility of the PBT framework for methodological joint-level analysis. Given the pilot scope and purposive elite sample, results are not intended for population inference but inform about methodological applications in training, rehabilitation, and injury-risk assessment. Full article

Background/Objectives: Cerebral palsy (CP) is a non-progressive, permanent syndrome of childhood, with approximately 80% of patients exhibiting spasticity. Untreated spasticity can cause pain, structural changes in bones, muscles, and nerves negatively impacting quality of life and functionality. Photobiomodulation (PBM) has demonstrated biological effects such as tissue regeneration, muscle relaxation, inflammation reduction, and pain relief. The objective of this pilot study is to evaluate the action of PBM on the spasticity of the medial and lateral right gastrocnemius muscles of children and adolescents with spastic cerebral palsy. Methods: This single-blinded, randomized, controlled trial evaluated PBM’s effect on gastrocnemius spasticity in children and adolescents with CP. The study presents pilot preliminary results from twelve children and adolescents (7–16 years) with spastic CP who were randomized into two groups: active PBM (850 nm, 100 mW, 1.5 J/point, 2 points, weekly for 8 weeks) or placebo (same protocol, device off). Both groups received standard rehabilitation exercises. Outcomes were assessed using the Modified Ashworth Scale (MAS), Pediatric Evaluation of Disability Inventory (PEDI), Gross Motor Function Classification System (GMFCS), and ankle range of motion before and after the intervention (8 weeks). Results: MAS and all outcomes improved significantly over time in both groups. No significant differences were found between groups for all outcomes. The PBM effect size on MAS improvement (ANOVA, Analysis of Vari, η² = 0.171) suggests modest but positive benefits. PBM did not worsen spasticity, and no adverse effects were reported. Conclusion: This study represents a pioneering effort in evaluating a safe PBM protocol for the spastics gastrocnemius in children and adolescents with CP. This protocol, used as an adjunct to physiotherapy, demonstrated no short-term adverse effects and no participant dropouts. Future studies should explore this PBM protocol in patients with less severe GMFCS levels, those with minimally preserved functionality, or those with contraindications to physiotherapeutic exercises. Full article

Background: The paralyzed ankles of stroke patients show reduced range of motion, muscle tightness, and joint stiffness, further impeding their ability to maintain balance and walk properly. This study aimed to investigate the effects of a combined joint mobilization and active stretching intervention on ankle stiffness, balance, and gait in patients with stroke. Methods: In this study, 24 stroke patients were assigned to two groups of 12 each: the control group (general physical therapy) and the experimental group (joint mobilization technique and active stretching exercise). All interventions were conducted for 30 min a day, 3 times a week, for a total of 4 weeks. Tension and stiffness of the gastrocnemius and tibialis anterior muscles were measured using Myoton^®PRO. Balance was evaluated using BioRescue, the Berg Balance Scale (BBS), and the Timed-Up and Go tests (TUG). All measurements were evaluated before the start of the intervention and after four weeks. Results: The muscle tone and stiffness of the medial and lateral gastrocnemius and tibialis anterior muscles of the experimental group were significantly improved compared with those of the control group. The experimental group had significantly increased moving areas in all directions and BBS scores compared with the control group. The experimental group showed a significant decrease in the time spent on the TUG test compared with the control group. Conclusions: We found that joint mobilization combined with active stretching intervention was more effective than general physical therapy in improving ankle joint movement, balance, and gait ability. Full article

The purpose of this study was to characterize the inter-segmental coordination of hip, knee, and ankle movement of the kicking leg during instep kicking for experienced athletes and novices, using vector coding as a non-linear technique. Motion capture and electromyographic data were collected for 14 soccer-majored college students and 32 novices performing the instep kicking task. The percentage of time spent on the coordination patterns, defined based on hip–knee and knee–ankle coupling angles, was calculated and compared. The agonist–antagonist activity ratio was calculated and compared. The time percentages of the knee–ankle shank dominance of the experienced athletes during the whole kicking movement were significantly greater than those of the novices (p < 0.050). Athletes achieving greater maximum ball speed had more knee flexion dominant coordination patterns in the back swing and leg-cocking, and knee extension dominant coordination patterns in the leg acceleration phase. The lower activity ratio of the tibialis anterior and gastrocnemius muscles contributed significantly to increasing kicking accuracy. These results underscore the value of vector coding in identifying key inter-segmental coordination features and directly support targeted soccer kick training. The dynamic stability exercises involving knee flexion and extension to optimize power transfer for speed, as well as activation and relaxation control exercises of the lower leg muscles to improve the kicking accuracy, may be effective ways to enhance instep kicking motor control ability and performance for soccer athletes. Full article

Recently, there has been growing interest in optimizing exercise protocols in sports training and rehabilitation, with particular attention to eccentric quasi-isometric (EQI) contractions, which involve maintaining joint position until isometric failure and then resisting the subsequent eccentric phase. Evidence directly comparing EQI with other contraction modes remains scarce. This quasi-randomized controlled trial examined the short-term effects of EQI versus isokinetic heavy–slow resistance (IHSR) exercises on ankle plantar flexors, focusing on pain, range of motion (RoM), and strength performance. Thirty-two physically active participants were allocated to EQI (n = 16) or IHSR (n = 16) groups and assessed at baseline, immediately post-exercise, and 24 and 48 h later. Both groups performed three exercise sets with 3 min breaks. The protocols were designed to approximate matched loading, based on preliminary testing. Nevertheless, the EQI group achieved a significantly greater total impulse (p = 0.028), a shorter time under tension (p = 0.001), and lower effort scores (p < 0.001). Group × time analysis revealed less decline in maximal voluntary isometric contraction torque (p = 0.002; η² = 0.16), as well as lower general (p < 0.001; η² = 0.32) and activity-related pain (p < 0.001; η² = 0.32) in the EQI group, with no significant differences in dorsiflexion RoM (p = 0.893). In conclusion, EQI produced a higher torque impulse while inducing less fatigue and post-exercise pain than IHSR, suggesting it may be a more efficient loading strategy for the ankle plantar flexors. The results contribute to the understanding of contraction-specific efficiency, and may inform the design of future training and rehabilitation protocols targeting the ankle plantar flexors. Full article

Background/Objectives: Lipedema is a chronic, progressive disorder of the adipo-fascial tissue characterized by abnormal subcutaneous fat accumulation, inflammation, fibrosis, pain, and edema. Despite its considerable impact on patients’ quality of life, it remains underdiagnosed. Recent studies have suggested a potential overlap between lipedema and hypermobility spectrum disorders (HSDs), both involving connective tissue dysfunction. This work explores the shared pathophysiological features of lipedema and HSD, highlighting clinical correlations, comorbidities, and the need for integrated diagnostic and therapeutic approaches. Methods: A cross-sectional observational study was conducted through an online survey targeting individuals with lipedema and a control group with lymphedema. The questionnaire assessed symptoms typically associated with HSD, including musculoskeletal, gastrointestinal, urogynecological, vascular, and neuropsychological manifestations. Descriptive statistics were used to evaluate clinical patterns in both groups. Results: Among the lipedema patients, 44% reported joint hypermobility and 60% recalled being hypermobile during childhood. High rates of pediatric overweight (50%), low muscle tone (55%), and exercise-induced fatigue (70%) were observed. Adult symptoms included joint pain (notably in the ankles, knees, cervical spine, sacrum, and feet), digestive issues (50%), and thyroid disorders (24.4%). Compared with the control group, patients with lipedema showed significantly more connective tissue-related motor deficits and systemic symptoms. Conclusions: Connective tissue laxity may play a critical role in the pathogenesis of lipedema, contributing to multisystemic manifestations through vascular, lymphatic, gastrointestinal, and musculoskeletal involvement. The high prevalence of HSD-like features calls for a paradigm shift in the understanding of lipedema as a systemic disorder. Early identification of connective tissue alterations, especially in children with familial predisposition, could enable timely interventions, potentially mitigating disease progression. A multidisciplinary, evidence-based approach is essential for accurate diagnosis and effective management. Full article

Background: Functional performance interlimb asymmetry may increase the risk of ankle sprains during basic military training. We aimed to (1) evaluate interlimb balance, agility, and ankle instability asymmetry in soldiers in infantry training as a risk factor for acute ankle sprains; (2) evaluate the effect of ankle sprains and sprain prevention exercise program on performance asymmetry. Methods: Newly inducted infantry soldiers were recruited from two induction cycles (intervention [INT] n = 365, control [CON] n = 421). Participants were assessed at the beginning of infantry basic training (T0) and after four months (T1) for anthropometrics, balance, agility, and perceived ankle instability, and were monitored for ankle sprains (SPRAIN/NO-SPRAIN). The INT group performed an ankle sprain prevention program 5 days/week × 5 min/day. Results: at T0 there were differences in interlimb asymmetry in Cumberland Ankle Instability Tool (CAIT) in SPRAIN soldiers in both groups (p-value < 0.001), and differences between the groups in Hexagon, Y-Balance Test (YBT) and CAIT (p-values 0.007, 0.002, 0.002, respectively). There was a decrease in interlimb asymmetry in Hexagon and YBT for SPRAIN soldiers in the INT group, and an increase in CAIT asymmetry in SPRAIN soldiers in both groups. Stepwise logistic regression did not find predictors for ankle sprains during training. Conclusions: The intervention program reduced interlimb asymmetry in balance and agility for soldiers who sprained their ankle during training. In these soldiers, CAIT asymmetry increased during training regardless of the intervention. Ankle sprain intervention programs should be implemented to reduce interlimb asymmetries in functional abilities and reduce the risk of injury. Full article

Background/Objectives: Getting up from the floor is an important functional skill for independence in older adults but is not often assessed clinically. The purpose of this study was to investigate how floor-to-stand transfer (FTS) ability is related to self-report measures and five-time sit-to-stand (5XSTS) performance, as well as compare peak joint angles during common FTS strategies and lower extremity demands between the 5XSTS and a commonly instructed FTS strategy. Methods: Thirty-four community-dwelling older adults completed self-report measures and performed the 5XSTS, a FTS in a self-selected manner, and an instructed FTS strategy. Biomechanical analysis of the lower extremities was used to determine peak joint angles, moments, and powers during study tasks. Correlation analyses were used to determine associations between FTS time and self-report scores, 5XSTS time, and lower extremity demands during the 5XSTS. One-way analysis of variance (ANOVA) and Kruskal–Wallis tests were used to determine the differences in self-report measures, 5XSTS performance, and FTS time between self-selected FTS strategies. Lower extremity demands between the 5XSTS and the instructed FTS strategy were compared with Wilcoxon Signed-Rank tests. Results: Self-report measures were not associated with FTS time or different between FTS strategies. Knee flexion was greater in the roll-over compared to the quadruped strategy (p < 0.001). Ankle and hip demands were greater during the instructed FTS, and knee demands were greater during the 5XSTS (p < 0.001) when comparing the tasks. Conclusions: The study findings may improve clinical decision-making related to FTS assessment and interventions in older adults. Prescribing exercises with greater hip and ankle demand than the 5XSTS may help maximize FTS ability. Full article