Search Results (71)

Growing use of inertial measurement units (IMUs) in velocity-based training has outpaced the evidence supporting their accuracy, making device-specific validation an essential aspect before adoption in research or practice. This study evaluated the concurrent validity of the GPath 6-axis inertial sensor against the Chronojump linear position transducer (LPT) for mean propulsive velocity (MPV) measurement during the bench press exercise. Twelve physically active males performed repetitions at 20%, 40%, 60%, and 80% of one-repetition maximum (1RM) across two separate testing sessions. Concurrent validity was evaluated using Pearson’s correlation, concordance correlation coefficient (CCC), Bland–Altman analysis, typical error, and coefficient of variation (CV). The GPath systematically overestimated MPV relative to the LPT at all loading conditions (p < 0.001), with bias decreasing from 0.253 m/s (20% 1RM) to 0.091 m/s (80% 1RM). CV remained low and consistent across conditions (5.12–5.98%). CCC was trivial > 1 m/s (20–40% 1RM: 0.079–0.056; combined: 0.331) and moderate < 1 m/s (60–80% 1RM: 0.430–0.433; combined: 0.833), with an overall CCC of 0.877. Between-session reproducibility of agreement was high (Session 1: CCC = 0.878; Session 2: CCC = 0.877), with between-session bias differences not exceeding 0.026 m/s. Despite its systematic overestimation, the GPath showed a reproducible bias structure between sessions, which may indicate utility for longitudinal within-athlete monitoring of relative MPV changes. Although, it cannot be recommended for absolute velocity measurement or 1RM estimation without prior correction. Full article

Background: Acute dehydration impairs performance, but its effects on resting neuromuscular and tissue mechanics are unclear. We tested whether baseline hydration status and exercise-induced sweat loss alter the resting neuromechanical phenotype of the rectus femoris (RF) as well as skin, subcutaneous tissue (subQ), and fascia overlying the RF. Methods: Thirty physically active men were randomized to hydration guidance (EXP) or habitual intake (CON). Hydration was verified weekly using first-morning urine specific gravity (USG), with targets of USG < 1.018 (EXP) and USG > 1.018 (CON). Participants performed continuous cycling at 50% maximal power output (Wmax) until ~3% body mass loss. Shear-wave elastography quantified tissue shear modulus (kPa), and tensiomyography assessed RF twitch-derived contractile properties (Dm, Tc, Tr) before and immediately after exercise. SWE data were analyzed using mixed design repeated-measures ANOVA; TMG outcomes were analyzed using non-parametric tests. Results: Baseline measures did not differ between groups. No significant group, time, or interaction effects were observed for RF muscle, skin, or subQ shear modulus. In contrast, fascia shear modulus showed a significant time effect, while TMG outcomes did not change significantly from pre- to post-exercise (all p > 0.05). Deep fascia showed a significant main effect of time, with decreased shear modulus post-exercise (F(1, 21) = 5.06, p = 0.035, η²p = 0.194; Δ = 1.25 kPa; d = 0.41; 95% CI [0.04, 0.78]), independent of hydration group. Conclusions: Under moderate-intensity cycling with approximately 3% body mass loss, we did not detect significant hydration-group differences or significant pre–post changes in resting RF twitch-derived contractile properties or in RF muscle, skin, and subQ shear modulus. Fascia shear modulus decreased after exercise irrespective of hydration group. These findings should be interpreted cautiously: the study was underpowered to detect small effects, and the fascial finding emerged from an exploratory, layer-specific analysis without correction for multiple comparisons. It should therefore be regarded as preliminary and hypothesis-generating, requiring confirmation in adequately powered, pre-registered studies. Full article

Background/Objectives: Promoting postural health in children requires not only adequate knowledge but also the implementation of health-promoting behaviors in the school environment. Teachers play a key role in this process; however, the extent to which their knowledge is reflected in everyday practice remains unclear. The study aimed to analyze and compare the levels of knowledge among preschool, early school, and physical education teachers regarding postural health in children and adolescents, including postural abnormalities, ergonomics, the selection of corrective exercises, and behaviors that promote correct body posture. Methods: A cross-sectional study was conducted on a sample of 153 teachers in Poland: 24 preschool (P), 53 early school education (EE), and 76 physical education (PE) teachers. The self-report Teachers’ Body Posture Literacy Questionnaire (TBPLQ) was used to assess knowledge regarding postural abnormalities. Results: PE achieved the highest TBPLQ scores, with significant differences observed mainly in comparison with EE (r = 0.30–0.50, p < 0.001). Across all groups, teachers performed best in recognizing postural abnormalities and worst in selecting appropriate corrective exercises. Although knowledge levels were relatively high, only weak correlations were found between knowledge and postural hygiene-promoting behaviors. The largest behavioral differences concerned the use of appropriate sportswear during physical education classes (η² > 0.14). Conclusions: Teachers demonstrated relatively high levels of knowledge regarding posture health. However, a clear knowledge–behavior gap was identified. Knowledge was only partially translated into proactive health-promoting actions, particularly regarding corrective interventions and communication with parents. The results suggest the need for educational initiatives for teachers focusing on proactive health-promoting and postural hygiene behaviors. Full article

Background/Objectives: Loneliness is a relevant social determinant of health in older age and has been associated with adverse physical, psychological and social outcomes. This study aimed to estimate the prevalence of severe loneliness and to identify its epidemiological and clinical correlates among community-dwelling older adults at risk of falls in Andalusia, Spain. Methods: A cross-sectional analytical study was conducted with 237 adults aged 65 years and older living in private households. Loneliness was assessed using the 10-item version of the UCLA Loneliness Scale, which showed excellent internal consistency in this sample (Cronbach’s alpha = 0.900). After reviewing the scoring direction of the instrument, severe loneliness was operationally defined using the corrected UCLA total score, with higher scores indicating greater loneliness. Sociodemographic and clinical variables included age, sex, living arrangements, economic level, family relationships, pain, sleep quality, depression history, physical exercise, outings from home, polymedication and analgesic use. Bivariate analyses were performed to compare participants with and without severe loneliness, and logistic regression was used to examine independent correlates of severe loneliness. Results: Severe loneliness was identified in 51 participants, corresponding to 21.5% of the analytical sample. The corrected UCLA-10 loneliness burden score ranged from 0 to 30, with higher scores indicating greater loneliness. Participants with severe loneliness were more likely to report poorer sleep quality and severe pain. In the adjusted logistic regression model including age, sex, sleep quality and severe pain, better sleep quality was associated with lower odds of severe loneliness (OR = 0.46, 95% CI: 0.30–0.72, p = 0.001), while severe pain was associated with higher odds of severe loneliness (OR = 3.15, 95% CI: 1.56–6.35, p = 0.001). Age (OR = 1.03, 95% CI: 0.99–1.07, p = 0.184) and female sex (OR = 2.00, 95% CI: 0.83–4.81, p = 0.124) were not statistically significant in the fully adjusted model. Conclusions: Severe loneliness affected a clinically relevant proportion of community-dwelling older adults at risk of falls in Andalusia. The findings should be interpreted as cross-sectional associations and not as evidence of causal pathways. Sleep quality and severe pain emerged as the main independent clinical correlates of severe loneliness in the adjusted model, supporting the relevance of multidimensional assessment in frail older adults. Full article

Smartphone-based augmented reality (AR) exercise systems show promise for supporting physical activity among older adults, yet the effect of presentation-layer information density on motor performance and cognitive workload in this population remains poorly understood. This study investigated how varying feedback density affects exercise correctness, error correction latency, and perceived workload in community-dwelling older adults (N = 60, aged 65–74 years) performing marching in place under three conditions: MIN, MOD, and RICH. The movement detection algorithm and binary correctness signal $C\left(t\right)$ were held invariant across conditions, isolating presentation-layer density as the sole manipulated variable. One-way repeated-measures ANOVA revealed significant density effects on all three outcomes. MOD produced the highest exercise correctness (M = 74.72%), shortest error correction latency (M = 2.45 s), and lowest perceived workload (M = 41.40); RICH yielded pronounced degradation across all measures. These findings provide preliminary empirical evidence consistent with a Capacity-Relative Density Equilibrium (CRDE) perspective, a conceptual framework that proposes performance as a zone-structured function of the demand-to-capacity ratio (D/K). The framework remains tentative and requires further empirical operationalization due to the lack of a direct measure of cognitive capacity (K). From this perspective, we identify three potential design principles, actionable sufficiency, density threshold, and dual-task alignment, as practical heuristics for mobile AR systems targeting older adult populations. Full article

Background: Equine-assisted programs have been shown to promote psychosocial outcomes, but quantitative evidence of motor benefits in correctional settings is scarce. Aim: The present study examined the effects of a one-week equine-assisted riding program on riding performance, movement quality, and well-being among young inmates in an open German prison. Methods: Ten male participants (24.5 ± 0.71 years) completed a five-day program combining practical riding exercises, cooperative activities, and guided reflection. Riding performance was assessed using standardized expert video ratings based on the German performance testing guidelines on a 10-point scale, movement quality using a semantic differential with bipolar adjective pairs assessing telic and autotelic dimensions on a six-point scale, and well-being using the WHO-5 Well-Being Index. A single-group pre–post repeated-measures design without a control group was applied. Results: Significant improvements were found in riding performance for both walk and trot, with large effect sizes (n = 10). Participants also reported a significant enhancement in the autotelic, experience-oriented dimension of movement quality, whereas no significant change occurred in the telic, goal-oriented dimension. Well-being increased significantly from pre- to post-test. Conclusions: Even a short, experience-focused equine-assisted program can produce meaningful improvements in motor performance, positive movement experience, and well-being in a correctional context. Equine-assisted programs may therefore represent a promising complementary approach to rehabilitation by integrating physical, emotional, and social learning processes. Full article

Barely Visible Impact Damage (BVID) in heterogeneous polymer-matrix composites remains difficult to detect because subtle damage signatures are often masked by complex architectures, hybrid textures, and overlapping failure morphologies. This study therefore presents an experimentally grounded, physics-aware, and statistically validated vision-based inspection framework rather than a purely detector-centered benchmarking exercise. Real post-impact images were obtained from controlled low-velocity impact experiments on 20 composite architectures and 60 physical specimens, yielding approximately 2000 images across laminated, hybrid, textile-reinforced, and sandwich structures. The dataset was organized using a specimen-disjoint splitting protocol to prevent leakage across training, validation, and test subsets. To improve robustness while preserving physical realism, a physically grounded Albumentations strategy was developed using only physically admissible transformations and explicit exclusion of non-physical operations that could distort damage morphology or surface continuity. Model development was further complemented by a hybrid hardware workflow in which cloud-based GPU training was combined with deployment-oriented inference profiling on resource-constrained edge-like hardware, thereby linking detection accuracy to practical industrial feasibility. In addition, model performance was evaluated under a standardized training budget and validated through repeated runs, Friedman significance testing, and Holm-corrected Wilcoxon signed-rank pairwise comparisons to ensure error-controlled interpretation of inter-model differences. Across the evaluated compact YOLO families, YOLO26s delivered the strongest overall performance, reaching 0.841 mAP@0.5, 0.586 ± 0.004 mAP@0.5:0.95, and an F1-score of 0.809, while YOLO11s achieved the highest precision and YOLO26n remained competitive in recall with nano-level compactness. Overall, the results show that experimentally generated heterogeneous composite data, morphology-preserving augmentation strategy development, leakage-aware dataset design, deployment-oriented computational profiling, and statistically grounded validation together provide a more robust and application-relevant basis for automated BVID detection in polymer-matrix composite structures. Full article

Sarcopenia is increasingly recognized as a key extracardiac manifestation of heart failure (HF), contributing to functional impairment, reduced quality of life, and adverse clinical outcomes. Characterized by progressive loss of skeletal muscle mass, strength, and physical performance, it affects more than half of hospitalized HF patients. It is independently associated with increased mortality and reduced exercise capacity. The pathophysiology of sarcopenia in HF is multifactorial and closely linked to metabolic and nutritional disturbances. Chronic inflammation, neurohormonal activation, oxidative stress, endothelial dysfunction, and anabolic resistance contribute to muscle catabolism and impaired protein synthesis. These alterations are further exacerbated by inadequate dietary protein intake and micronutrient deficiencies, promoting progressive muscle wasting and functional decline. Sarcopenia may also represent an early and potentially modifiable stage in the continuum toward cardiac cachexia. This narrative review provides a comprehensive synthesis of current evidence on the epidemiology, pathophysiological mechanisms, and management of sarcopenia in HF, with particular emphasis on nutritional and metabolic determinants. Emerging data support a multimodal therapeutic approach integrating exercise training with targeted nutritional strategies, including adequate protein intake, essential amino acid supplementation, and correction of micronutrient deficiencies. However, evidence from large, well-designed trials remains limited. In summary, improved recognition and integrated management of sarcopenia in HF are essential. Future research should focus on the development of effective, nutrition-centered therapeutic strategies. Full article

Systemic inflammation is influenced by regular physical activity and diet. While moderate exercise can transiently alter inflammatory markers, high-intensity activity may increase muscle turnover without substantially elevating systemic inflammation. The combined effects of physical activity and dietary inflammatory potential in healthy young men remain poorly defined. In this cross-sectional observational study, 233 healthy men aged 18–30 years were categorized according to physical activity level: low (NA, n = 52), moderate (A, n = 93), and high (S, n = 88). Anthropometry and body composition were assessed using bioelectrical impedance. Dietary intake was recorded over 4 days and used to calculate the Dietary Inflammatory Index (DII). Blood samples were collected and analyzed for complete blood counts, high-sensitivity C-reactive protein (hs-CRP), serum amyloid A (SAA), and creatine kinase (CK). Differences between groups were evaluated using the Kruskal–Wallis test with Dunn’s post hoc correction, and principal component analysis (PCA) was performed to explore multivariate inflammatory patterns. The highest BMI, fat percentage, and DII were observed in low-activity men, whereas fat-free mass and CK activity were greatest in highly active men. Slightly higher systemic inflammatory markers (hs-CRP and SAA) were observed in moderately active men compared to other groups. PCA revealed two principal axes: PC1 representing systemic inflammation and PC2 representing leukocyte distribution. Weak associations were found between DII and these components, indicating a limited link between dietary inflammatory potential and circulating inflammatory biomarkers. Body composition is strongly influenced by physical activity, with high activity promoting lean mass and moderate activity associated with modest elevations in inflammatory markers. Dietary inflammatory potential was only weakly associated with systemic inflammation, suggesting that exercise-induced physiological stress may play a more prominent role in shaping inflammatory profiles in healthy young men. Full article

The physiological and hematological responses to exercise and the corresponding adaptations in high-level sports have become an important issue, from both the health and the physical performance points of view. This study investigated the fluctuations in physiological and hematological variables of young swimmers throughout a training season. Twelve well-trained male swimmers (age: 14 ± 0.3 y) participated in the study. Measurements were carried out at the beginning of the training season (T1) and pre and post the taper of each of the two competitive periods (i.e., T2, T3 for the first training macrocycle, and T4, T5 for the second macrocycle, respectively). At each of the above time points, maximum oxygen uptake (VO_2max) was estimated, and blood samples were collected before and 1 h post a maximal 400 m swimming testing to measure hemoglobin (Hb), hematocrit (Hct), mean corpuscular volume (MCV), mean cell hemoglobin (MCH), mean cell hemoglobin corpuscular (MCHC), platelets (PLT), red blood cells (RBCs), and albumin (Alb). Adjustment for exercise-induced plasma volume changes was performed before all data analyses. Analysis of variance (ANOVA) with repeated measures followed by Bonferroni post hoc analyses was used for statistics. Multiple correlations with Bonferroni correction were also performed. Significant improvement of performance from T1 to the end of the study was recorded. Moreover, significant changes in lactate concentration ([La⁻]) with significant decrease at T3 and increase at T4 were also observed. Significant interaction (pre–post-test × test condition) for Hct, Hb, MCV, MCH, and RBCs; the main effect of test condition for Hct, MCV, MCHC, PLT, and Alb; and pre–post-test for Hct, Hb, MCV, MCHC, and RBCs were observed. No significant changes for VO_2max and HR were recorded (p > 0.05). Significant correlations between MCV and MCH at T1, T2, T4, and Hct and Hb at T1, T4, T5 were found. These results indicate that swimming training throughout a season induces both acute and long-term effects on the physiological and hematological profile of young swimmers. These findings provide fundamental information about the effects of the training volume and intensity on physical performance and might be utilized as a useful source for future studies to further characterize the systemic and performance signature of training-induced adaptations during a competitive season in swimmers. Full article

Background: Age-related cognitive decline is linked to reduced gait complexity and higher fall risk. Traditional linear gait measures may miss subtle motor-cognitive deficits in older adults with dementia. This study examined whether an 8-week motor-cognitive exercise program could improve gait adaptability in institutionalized older adults with cognitive impairment. Gait complexity, measured using Sample Entropy, was the primary outcome. Methods: Forty-two institutionalized older adults completed follow-up assessments, including 26 with cognitive impairment and 16 controls. Gait was assessed during normal walking (single-task) and while performing cognitive tasks (dual-task), such as naming animals or counting backward. Inertial sensors recorded stride intervals, and Sample Entropy was calculated to evaluate gait regularity and adaptability, (gait complexity). The intervention included 24 structured sessions combining physical and cognitive exercises targeting balance, coordination, and executive function. Non-parametric tests (Wilcoxon) were used, with Bonferroni correction for multiple comparisons. Results: Participants with cognitive impairment showed increased gait complexity, especially during dual-task walking. Significant improvements were found in both limbs under dual-task conditions (left: p = 0.015, effect size = 0.34; right: p = 0.030, effect size = 0.31). During single-task walking, a significant improvement was observed in the left limb (p = 0.006, effect size = 0.39). Conclusions: Motor-cognitive exercise may enhance non-linear gait complexity in institutionalized older adults with cognitive impairment. The use of dual-task training in rehabilitation and highlight the value of entropy-based gait assessment for detecting subtle functional changes. However, the lack of a randomized non-exercising cognitive impairment control group limits definitive conclusions about causality. Full article

Background: Basketball performance depends strongly on physical preparation. A novel approach is accentuated eccentric loading within contrast training, though its acute effects using dumbbells remain underexplored. Methods: Twelve youth basketball players (age = 16.0 ± 0.3 years; body mass = 81.5 ± 7.6 kg) completed three sessions with dumbbell loads equivalent to 15%, 30% and 45% BW. CMJ performance was measured using dual wireless dual force plates. Assessments were conducted before the protocol and at 3, 9, and 15 min post intervention. Subjective responses were collected via wellness, RPE and readiness questionnaires. A two-way repeated measures ANOVA with Bonferroni corrections was applied, and the significance level was set to α = 0.05. Results: Significant decreases in jump height (p = 0.010) and average propulsive power (p = 0.005) were observed in the 45% BW condition at 3 and 9 min. Jump momentum decreased significantly at 30% and 45% BW at 3 and 9 min (p = 0.010; p = 0.033). No significant differences were detected in other CMJ force–time metrics (p > 0.05). Conclusions: Dumbbell-loaded CMJs as an accentuated eccentric loading contrast exercise did not produce generalized improvements but induced acute decreases at higher loads. However, they may still be useful in individual cases for athletes with favorable responses after monitoring. Full article

Objectives: Connective tissue dysplasia (CTD) is associated with disorders of collagen synthesis and is widely spread among the healthy population and people with disabilities. In the heart, primarily in the left ventricle (LV), CTD manifests itself as the formation of false tendons (LVFTs) to maintain close-to-normal LV pump function. This exploratory work is devoted to the search for general patterns of cardiac response to physical activity in athletes with disabilities, CTD, and LVFTs. The extent to which “the type of sports or the type of disability” determines the involvement of the heart’s functional reserve is the main testable question of the proposed research. Methods: The group under this study included 610 individuals with disabilities aged from 6 to 60 years with at least two transverse and/or oblique FTs per LV. Participants represented different sports disciplines (n = 10) and various forms of disabilities (n = 4). Cardiovascular indicators were obtained by means of standard TTE, impedance cardiography for hemodynamic monitoring in active orthotest, resting, and stress 12-lead ECG. Exercise testing of the athletes was performed with the use of appropriate methods of physical loading. In total, 141 parameters of cardiorespiratory function and exercise performance per participant were recorded. Statistical analysis of the dataset obtained across sports types or disability types was performed using one-way ANOVA or the Kruskal-Wallis test, depending on the assumptions of normality and homogeneity of variance. Results: Most importantly, it was found that only maximum relative oxygen consumption (VO₂max, mL·kg⁻¹·min⁻¹) as a reliable indicator of the heart’s functional reserve and the corrected QT (QTc, ms) interval as an integral measure of the heart’s electrical activity demonstrated statistically significant differences across the sports specialization or the disability type. In particular, significance values (P) for VO₂max across athletic disciplines and nosology categories were equal to 0.00063 and 0.01028 (one-way ANOVA), while for QTc they were 0.00001 and 0.02185 (Kruskal-Wallis), respectively. Furthermore, the type of disability had a lower impact on VO₂max and QTc than the type of athletic activity. Conclusions: In athletes with disabilities and CTD, sport specialization may involve the heart’s functional reserve to a greater extent than the type of disability. To prescribe training loads for people with disabilities and CTD, individual cardiology screening with an emphasis on VO₂max and QTc is necessary. Full article

Virtual reality (VR) technologies are increasingly applied in rehabilitation, offering interactive physical and spatial exercises. A major challenge remains the objective assessment of human movement quality (HMQA). This study aimed to identify biomechanical features differentiating correct and incorrect execution of a lateral lunge and to determine the minimal number of sensors required for reliable VR-based motion analysis, prioritising interpretability. Thirty-two healthy adults (mean age: 26.4 ± 8.5 years) performed 211 repetitions recorded with the HTC Vive Tracker system (7 sensors + headset). Repetitions were classified by a physiotherapist using video observation and predefined criteria. The analysis included joint angles, angular velocities and accelerations, and Euclidean distances between 28 sensor pairs, evaluated with Linear Discriminant Analysis (LDA) and SHapley Additive exPlanations (SHAP). Angular features achieved higher LDA performance (F1 = 0.89) than distance-based features (F1 = 0.78), which proved more stable and less sensitive to calibration errors. Comparison of SHAP and LDA showed high agreement in identifying key features, including hip flexion, knee rotation acceleration, and spatial relations between headset and foot or shank sensors. The findings indicate that simplified sensor configurations may provide reliable diagnostic information, highlighting opportunities for interpretable VR-based rehabilitation systems in home and clinical settings. Full article

An important aspect of medical rehabilitation using exoskeletons is objective monitoring of the effectiveness of the exercise program. This control is most often manual and relies on the attention of a rehabilitation physician, but advanced rehabilitation systems also use computer vision technology. Topological skeletons generalize large areas of digital images, representing a virtual internal framework of the analyzed object. The patient and the exoskeleton are described either as a set of spatially disparate (but not explicitly related to either the patient or the exoskeleton) topological skeletons, or as branches of a single topological skeleton which does not allow for objective monitoring of joint displacements. A method to solve this problem for medical rehabilitation using an upper-limb exoskeleton is proposed. It includes the following stages: (I) identifying the exoskeleton, as well as upper and lower parts of the patient’s body; (II) independent construction of three topological skeletons (separately for the exoskeleton and for the upper and lower parts of the patient’s body); (III) their integration. This approach allows for accurate, real-time analysis of movements in the upper-limb joints and prompt notification to the rehabilitation physician of any significant deviations in the technique of performing prescribed exercises. Full article