Journal of Functional Morphology and Kinesiology

Objectives: The Arch Index (AI) is commonly used to assess medial longitudinal arch morphology; however, values obtained using different measurement technologies may not be interchangeable. This study aimed to compare AI values derived from optical pedography and a barometric platform during bilateral static stance assessment in children and to evaluate their agreement. Methods: Thirty-eight healthy children aged 5–10 years underwent standardized bilateral static foot assessment. AI was calculated using identical segmentation and formula for both systems. Paired t-tests, Pearson correlation, intraclass correlation coefficient, and Bland–Altman analysis were used to assess agreement between methods. Results: Optical pedography produced significantly higher AI values than barometric assessment for both the left (0.284 ± 0.055 vs. 0.188 ± 0.092) and right foot (0.286 ± 0.048 vs. 0.169 ± 0.072; p < 0.001). Agreement between methods was moderate (ICC = 0.494–0.581), with wide limits of agreement. Inter-method differences increased with age. Conclusions: AI values obtained from optical pedography and barometric platforms are not interchangeable in children. Consistent use of a single measurement technology is recommended in pediatric assessment to avoid misinterpretation of developmental changes. Full article

Objectives: This study aimed to evaluate the effects of a combined treatment consisting of O₂O₃ injections and McKenzie-based physiotherapy exercises, compared to a Control group treated with O₂O₃ injections and a Back School physiotherapy program, in reducing pain and disability in individuals with chronic non-specific neck pain. Methods: In this prospective double-arm pilot study, patients with chronic non-specific neck pain and a Numerical Rating Scale (NRS) > 4 were enrolled. All patients received eight weekly sessions of O₂O₃ injections (10 μg/mL, 10 mL total, and 2 mL bilaterally into the cervical paravertebral muscles). Patients were then randomly assigned (1:1 ratio) to either an experimental group receiving McKenzie physiotherapy or a Control group undergoing Back School techniques, with five sessions per week over two weeks. Outcome measures included the Neck Disability Index (NDI), NRS, EuroQol-5D-3L (EQ5D3L), and EuroQol Visual Analog Scale (EQ-VAS). Results: A total of 41 patients were included and divided into two groups: Back School (n = 21; mean age: 63.9 ± 13.4 years) and McKenzie (n = 20; mean age: of 57.3 ± 12.9 years). Both groups showed significant improvement in NDI, NRS, EQ5D3L, and EQ-VAS following the O₂O₃ injection cycle (∆T0–T1 p < 0.001). The subsequent addition of physical therapy led to further improvements across all outcomes in both groups (∆T1–T2 p < 0.001), with the McKenzie group showing slightly greater benefits, despite the lack of significant differences. Conclusions: This study demonstrated the effects of combining O₂O₃ injections with either McKenzie or Back School therapy in improving pain, disability, and quality of life in patients with chronic non-specific neck pain. Full article

Objectives: Circadian rhythms regulate key physiological processes, including metabolism and energy balance. Emerging evidence suggests that the timing of physical activity may influence metabolic outcomes. However, how the timing of endurance exercise impacts long-term metabolic health and the role of the circadian clock in this process remain unclear. This study aimed to investigate whether time-dependent endurance exercise improves metabolic health via circadian rhythm regulation. Methods: A 12-week endurance exercise protocol was established using wild-type (WT) and circadian-disrupted Clock^Δ19 mice. Mice were assigned to exercise at Zeitgeber time 0 (ZT0) or Zeitgeber time 0 (ZT12), or to sedentary controls. Assessments included rotarod fatigue test, body weight, epididymal fat ratio, fasting blood glucose, serum triglycerides, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), non-esterified fatty acids (NEFA), intraperitoneal glucose tolerance test (IPGTT), and insulin tolerance test (ITT). Results: Clock^Δ19 mice exhibited circadian phase-dependent fatigue susceptibility on the rotarod, particularly at ZT0. Both exercised Clock^Δ19 groups (ZT0 and ZT12) showed significant weight reduction compared to sedentary controls, indicating that endurance exercise may counteracts circadian disruption-induced weight gain independent of timing. In WT mice, evening exercise (ZT12) led to enhanced lipid regulation and better glucose tolerance. These time-dependent benefits were absent in Clock^Δ19 mutants, demonstrating that the full metabolic advantages of exercise require a functional circadian clock. Notably, endurance training also partially restored serum HDL-C levels in Clock^Δ19 mice, suggesting compensatory metabolic responses. Conclusions: Aligning endurance exercise with the body’s internal clock provides greater metabolic benefits than untimed exercise. The circadian clock is essential for time-dependent improvements in glucose and lipid metabolism, although some beneficial effects occur independently of a functional clock. Full article

Background: Proximal lower-extremity muscle strengthening is an important conservative intervention for patellofemoral pain syndrome (PFPS), as these muscle groups play critical roles in femoral stabilization and knee valgus control. However, evidence remains limited regarding the effectiveness of muscle strengthening in improving lower-extremity axial alignment through modulation of femoral neck anteversion, femoral internal rotation, and tibial external rotation. Therefore, the present study aimed to determine whether a strengthening protocol targeting the quadriceps and hip external rotator and hip abductor muscles could improve knee alignment and reduce bone torsion in young adults with patellofemoral pain syndrome. Methods: This prospective interventional cohort study implemented a muscle strengthening protocol in ten university students with PFPS. Outcomes included femoral neck anteversion angle (FNA), tibial tubercle–trochlear groove distance (TT–TG), tibial external torsion angle (TET), and the knee Q-angle, assessed via 3D reconstruction of computed tomography (3D-CT) images. Pre- and post-intervention data were analyzed using the Shapiro-Wilk test for normality and repeated-measures ANOVA (p < 0.05; 95% confidence interval). Results: Muscle strengthening improved lower-limb axial alignment, with reductions observed across all measures post-intervention. Mean changes were 0.68 ± 1.26° for FNA (p = 0.0626); 1.51 ± 0.97 mm for TT–TG (p = 0.0001); 1.38 ± 3.36° for TET (p = 0.2231); and 1.14 ± 1.52° for the Q-angle. Statistically significant improvements were observed for TT–TG and the Q-angle. Conclusions: Proximal muscle strengthening improved knee valgus and axial lower-limb alignment, as evidenced by significant reductions in Q angle and TT–TG distance. Reductions in femoral neck anteversion (FNA) and tibial external torsion angle (TET) were observed. However, these differences were not statistically significant. These findings support muscle strengthening as a noninvasive strategy for improving lower-limb alignment in individuals with patellofemoral pain syndrome. Full article

Background: Chronic shoulder pain associated with subacromial bursitis is a common clinical condition characterized by pain and functional limitation, factors that contribute significantly to chronic morbidity for the patient. The combination of ultrasound-guided corticosteroid injections and physical therapy may improve clinical outcomes. This study compared the effectiveness of Proprioceptive Neuromuscular Facilitation and standardized exercise-based physiotherapy after a common protocol of ultrasound-guided corticosteroid injections in patients with chronic shoulder pain associated with subacromial bursitis. Methods: A randomized controlled pilot study was conducted on adult patients with chronic shoulder pain (NRS ≥ 4), who received 3 weekly intra-bursal ultrasound-guided injections of corticosteroids and local anesthetic, followed by either 10 sessions of PNF or standardized exercise-based physiotherapy. The primary outcome was pain intensity assessed by NRS. Secondary outcomes included DASH, EQ-5D, EQ-VAS, and ROM, assessed at baseline, 2 weeks, 4 weeks, 12 weeks, and 24 weeks. Results: The PNF group showed greater improvements in selected outcomes and at some follow-up time points, particularly for functional measures and shoulder ROM. However, between-group differences were not consistent across all predefined outcomes. Conclusions: Both PNF-based rehabilitation and standardized exercise-based physiotherapy may improve clinical outcomes after ultrasound-guided corticosteroid injection in patients with subacromial bursitis. However, the added value of PNF appears limited to selected outcomes and time points, and its superiority over standardized physiotherapy cannot be definitively established. Full article

Background: Functional testing after an ankle sprain may help identify patients who later develop mechanical instability and require surgery. This study aimed to identify early clinical and functional predictors of surgical stabilization for chronic ankle instability (CAI) after acute sprains and to develop a simple composite predictive score (TALAR). Methods: This prospective observational study included 197 patients with acute lateral ankle sprains. Comprehensive clinical and functional assessments, including range of motion (ROM), strength, and pain, were performed two weeks post-injury. The primary outcome was subsequent surgical management for instability within a 24-month follow-up period. Results: Eight patients (4%) ultimately underwent surgical stabilization. Univariable analysis identified three significant predictors of surgical outcome: eversion mobility ≥ 20°, plantar flexor strength ≤ 17 kg, and the presence of pain during dorsiflexion (VAS > 0). These variables were integrated into the 0–3 TALAR (Triage Assessment of Lateral Ankle sprain Surgical Risk) score, which demonstrated promising exploratory discrimination with an AUC of 0.889 (95% CI: 0.799–0.954). An optimal cut-off of ≥2 yielded a sensitivity of 0.875 and a specificity of 0.822. While the baseline surgical risk was 4%, patients with a TALAR score ≥2 had a 17.5% conversion rate to surgery, representing a significantly higher risk (OR: 32.24; p < 0.001). Conclusion: The TALAR score represents a promising exploratory tool for early risk stratification after an acute ankle sprain. As an exploratory study, it highlights that early functional red flags, though formal internal and external validation, along with robust calibration on longer follow-up cohorts, are required before clinical implementation. Full article

Background: Wushu, a traditional Chinese exercise, has been demonstrated to be effective in promoting lower-limb strength in children. However, studies comparing the effects of different intervention durations on preschool children remain limited. Objectives: The present study examined the short- and long-term effects of Wushu exercise programs on lower-limb explosive power in preschool children aged 5–6 years. Methods: This study was conducted across two experiments, with separate cohorts of children. The children were randomly assigned to either an intervention (INT) or a control (CON) group based on their Kindergarten classes. In Experiment 1, the INT-1 group (n = 55) completed a 4-week ‘Twelve Zodiac’ Wushu exercise program, which comprised three 30-minute sessions per week, while the CON-1 group (n = 49) participated in construction and carrying-based unstructured free play, which was designed to provide a comparable amount of moderate-to-vigorous physical activity. In Experiment 2, the INT-2 group (n = 57) undertook a 10-week Wushu program, and the CON-2 group (n = 38) engaged in similar activities as CON-1 for a 10-week period. The standing long jump (SLJ) was the primary outcome measure in both experiments. Secondary outcomes included the double-leg continuous jump, 15 m zigzag run, grip strength, sit-and-reach, and anthropometric measurements. In Experiment 2, countermovement jump (CMJ) and squat jump (SJ) heights were also measured using a force plate as additional secondary outcomes. A linear mixed-effects model (LMM) was used to analyze the data. Results: At baseline, no significant outcome measures were observed between CON-1 and INT-1, nor between CON-2 and INT-2. In Experiment 1, SLJ exhibited a significant enhancement in INT-1 in comparison to CON-1 (p = 0.007). The INT-2 in Experiment 2 showed significant improvements compared with CON-2 in the SLJ (p = 0.048), double-leg continuous jump (p = 0.005), and 15 m zigzag run (p = 0.043). A strong correlation was observed between SLJ and 15 m zigzag run time (r = −0.53, p < 0.001), and between double-leg continuous jump time and 15 m zigzag run time (r = 0.56, p < 0.001). Conclusions: The findings of this study indicate that 4-week and 10-week Wushu exercise programs enhance explosive power in the lower limbs of children aged 5–6 years. The 10-week Wushu program improves lower limb coordination and jumping agility. These task-specific adaptations support the value of Wushu interventions for fostering comprehensive lower-limb motor competence in preschoolers. Full article

Background: Maximal isometric co-contraction (MICC) of upper-limb muscles enhances strength and size, but its effects on lower-limb function are unknown. The aim of this study was to examine whether MICC training targeting the lower limbs can improve muscular strength and functional performance in sedentary adults. Methods: Twenty sedentary individuals (10 men, 10 women; 48.5 ± 7.5 years; BMI = 24.8 ± 4.2 kg/m²) were randomly assigned to either an experimental (EXP) or control (CON) group. The EXP group performed MICC of the knee flexors and extensors three times per week for four weeks, completing three sets of 5–10 maximal effort 3 s contractions per session. Assessments conducted pre- and post-intervention included the isometric mid-thigh pull (IMTP), 3-m timed up and go (TUG), and 30 s chair stand (CS) tests. Results: Significant time (p < 0.001) and time × group (p < 0.001) effects were found for all outcomes. Compared with CON, the EXP group showed greater improvements in IMTP peak force (p < 0.001, g = 1.80), faster TUG times (p < 0.001, g = 2.73), and more CS repetitions (p < 0.001, g = 3.90). Conclusions: Twelve sessions of MICC training improved maximal strength and functional performance in sedentary adults. This simple, equipment-free method may be particularly useful for individuals with limited access to conventional exercise facilities or supervision. Full article

Objectives: Treadmill walking is often employed for tightly controlled gait and energetics research, but growing evidence suggests that treadmill-based metabolic and biomechanical measurements may not directly reflect the ecologically valid mode of overground walking. While many previous studies focused on older adults, much less is known about how treadmill walking influences gait energetics and spatiotemporal parameters in young healthy adults across matched speeds. We investigated energy expenditure, metabolic cost of walking and spatiotemporal gait parameters in healthy young adults walking overground and on a treadmill at three speeds (slow—1.0, comfortable—1.3, fast—1.5 m/s). Our hypothesis was that at the comfortable speed, treadmill and overground energetics and gait parameters would be comparable. However, at slow and fast speeds, there would be a significant energetic penalty, accompanied by significant differences in spatiotemporal parameters. Methods: Twenty young participants (10 males and 10 females) completed a randomized cross-over walking protocol with a minimum of ten minutes treadmill familiarization at 1.3 m/s. Breath-by-breath oxygen consumption ($\dot{V}{O}_2$) and Respiratory Exchange Ratio were measured using a portable indirect calorimetry system and gait parameters were calculated from Inertial Measurement Units. Gross and net energy expenditures, costs of walking, cadence, average step and stride lengths, and walk ratio were calculated. A three-way mixed ANOVA was used for primary statistical analyses. Results: Treadmill walking was characterized by higher gross and net energy expenditures and metabolic costs (p < 0.001, η_p² = 0.6) across all speeds compared to overground. It was also characterized by faster cadence and shorter average step and stride lengths (p < 0.001, η_p² = 0.9). Additionally, there was an effect of sex (p = 0.01, η_p² = 0.3) on the gait parameters, with females exhibiting a faster cadence and shorter average step and stride lengths than males. Conclusions: Our findings show that treadmill walking imposes a medium-to-large metabolic penalty even in healthy young adults, with compensatory gait adaptations, possibly reflecting increased stabilization demands and altered neuromuscular control strategies. These results underscore the limits of generalizing treadmill derived gait data to overground walking and we caution against the uncritical use of treadmills, especially while trying to understand ecologically relevant human walking mechanics and energetics. Full article

Background: Aquatic therapy has emerged as a promising rehabilitation strategy for people with multiple sclerosis (MS), potentially improving physical and psychological outcomes through the unique properties of water. The aim of the study was to systematically evaluate the effects of aquatic therapy on fatigue, mobility, physical function, and quality of life (QoL) in people with MS. Methods: A systematic review and meta-analysis were conducted following PRISMA guidelines. Electronic databases (PubMed, Scopus, Web of Science, PEDro, CINAHL, and Cochrane) were searched from inception to February 2026. Eligible studies included adults with MS undergoing aquatic therapy interventions. Risk of bias and methodological quality was assessed using the Cochrane tool and the PEDro scale, respectively. Effect sizes were calculated as standardized mean differences (SMD) using a random-effects model. Results: Seven randomized controlled trials (RCTs) were included in the review. Meta-analysis demonstrated a large reduction in fatigue (SMD ≈ −1.20), moderate improvements in mobility and physical function (SMD ≈ 0.7), and small-to-moderate improvements in QoL (SMD ≈ 0.45) in favour of aquatic therapy. Heterogeneity ranged from moderate to high depending on the outcome. Qualitative synthesis supported these findings and indicated additional benefits in strength, balance, psychological well-being, and disease-related symptoms. No adverse events were reported. Conclusions: Aquatic therapy may represent a generally well-tolerated and potentially beneficial rehabilitation strategy for improving fatigue, mobility, and QoL in people with MS. However, these findings should be interpreted with caution due to the limited number of included RCTs, relatively small sample sizes, and substantial heterogeneity across interventions and outcome measures. Full article

Objectives: In lifeguarding, when prevention fails, rapid and safe rescue is essential to prevent submersion and enable appropriate care. These operations demand high physical fitness. High-Intensity Functional Training (HIFT), such as CrossFit^®, has become a widely used training model. This study examined the integration of HIFT into lifeguard training to enhance preparedness for aquatic rescues. The aim was to analyse the external and internal load generated by a lifeguard-specific HIFT protocol and to assess its utility both as a training method and as a fitness evaluation tool. Methods: Twenty-seven lifeguards completed a 15 min HIFT protocol in an AMRAP (As Many Rounds As Possible) format with four stations: running, swimming with a tow, victim extraction, and cardiopulmonary resuscitation (CPR). Variables measured included time per round (TRound), number of completed rounds, maximum and average heart rate (MaxHR, AvgHR), post-exercise blood lactate, rating of perceived exertion (RPE) per round and overall, and CPR quality (Q-CPR). Results: TRound ranged from 238 to 268 s, with significant differences between consecutive rounds, though remaining at submaximal levels. Most participants (74%) completed three rounds, and none completed four. AvgHR was 164 bpm (82% of MaxHR). RPE increased significantly across rounds (p < 0.001), reaching 9 post-AMRAP (p < 0.001). Post-AMRAP blood lactate was 15.50 mmol/L (p < 0.001), indicating high physiological stress. Despite accumulated fatigue, Q-CPR remained consistently high, ranging from 86% to 94%, with no significant differences across rounds. Conclusions: The results of this pilot study suggest that physically active lifeguards can sustain a controlled, high-intensity effort at submaximal heart rates and high perceived exertion without compromising CPR quality. These preliminary findings support the feasibility and potential utility of a lifeguard-specific HIFT programme structured as an AMRAP for high-intensity training and ecological fitness assessment in rescue-specific conditions; formal validation studies are needed before broader recommendations can be made. Full article

Background: Physical inactivity and sedentary behaviour are major public health concerns associated with an increased risk of non-communicable diseases, reduced quality of life, and substantial healthcare burden. In recent years, technology-based interventions, including wearable devices, mobile health applications, artificial intelligence-driven systems, and adaptive digital platforms, have been increasingly adopted to promote physical activity and reduce sedentary time in adult populations. However, the evidence remains fragmented across intervention types, behavioural targets, and population groups. The aim of this scoping review was to map the recent literature on digital interventions designed to promote active lifestyles in adults, with a specific focus on their reported impact on physical activity promotion and sedentary behaviour reduction. Methods: This scoping review was conducted in accordance with the PRISMA-ScR guidelines. A literature search was performed in PubMed and Scopus using a predefined search strategy combining terms related to digital technologies, physical activity, sedentary behaviour, and adult populations. Studies published in English between 2022 and 2026 were considered. After removal of duplicates and screening of titles and abstracts, full texts were assessed according to predefined eligibility criteria. Data were charted descriptively and synthesised narratively to identify the main intervention models and emerging research trends. Results: The search identified 887 records, of which 35 studies were included in the final synthesis. The literature included was grouped into four broad categories: wearable devices and mHealth tools for monitoring and goal-setting; adaptive interventions based on Just-In-Time Adaptive Interventions, artificial intelligence, and gamification; advanced technologies such as Internet of Things systems and exoskeleton-based approaches; and hybrid interventions combining digital tools with human support or environmental modifications. Overall, technology-based interventions were generally associated with increases in step count, moderate-to-vigorous physical activity, and adherence to movement-related behaviours. In contrast, their effectiveness in reducing sedentary behaviour was less consistent and appeared to depend more strongly on context-sensitive prompting, posture-focused strategies, and multicomponent or hybrid intervention models. Conclusions: Digital health interventions represent a promising strategy for promoting physical activity in adults, but their impact on sedentary behaviour reduction remains more limited and heterogeneous. The findings suggest that simply increasing exercise is not sufficient to address prolonged sitting and that more tailored, adaptive, and context-aware approaches are needed. Future research should prioritise methodological standardisation, longer follow-up periods, and interventions specifically designed to interrupt sedentary time across different adult populations. Full article

Objectives: This study investigated bilateral strength asymmetry, the bilateral asymmetry index, and the bilateral deficit ratio during one-repetition maximum leg press testing performed under bilateral, unilateral, and split-load conditions and examined their associations with isokinetic knee and hip strength asymmetries. Methods: 31 resistance-trained males completed 1RM leg press tests in all loading modes, followed by isokinetic knee flexion/extension and hip extension assessments at 60°·s⁻¹. Results: The repeated measure ANOVA showed that split-load leg press had a significantly greater bilateral deficit ratio (14.29 ± 7.71%) compared to the bilateral condition (5.16 ± 9.60%, p < 0.001). Isokinetic testing showed significant inter-limb differences for knee flexion and extension but not hip extension. The bilateral strength asymmetry varied across tasks (5.17 ± 4.44% in leg press to 17.84 ± 12.40% in eccentric hip extension), while bilateral asymmetry index remained consistently lower. Bilateral strength asymmetry differed significantly across leg press conditions, whereas the bilateral asymmetry index did not. Knee flexion bilateral asymmetry index correlated with dominant and non-dominant hamstring to quadriceps ratios (respectively, r = 0.61; r = 0.37) and cross-limb flexor–extensor ratios (r = 0.42). No significant relationships were found for hip extension asymmetry. Conclusions: Split-load leg press might be used to test lower limb bilateral deficit, because it provides easily detectable deficit values. Unilateral leg press might be used to detect lateral strength differences, since it provides relation to isokinetic strength of knee flexors and extensors. Full article

Background: Biological maturity assessment is increasingly discussed in youth sport because chronological age alone does not reflect inter-individual variation in growth and pubertal timing. Ultrasound-based systems such as BAUSport™ provide a radiation-free alternative to radiographic skeletal age assessment. This exploratory cross-sectional study examined skeletal age (SA) in Slovak female volleyball players, track-and-field athletes, and non-athletes using BAUSport™, while acknowledging substantial age differences between groups. Methods: Eighty girls (55 non-athletes, 13 volleyball players, 12 track-and-field athletes; aged 6.85–14.41 years) underwent anthropometric measurement and skeletal age (SA) assessment with BAUSport™. Chronological age (CA) was calculated as decimal age from birth date to measurement date. Groups were not age-matched; volleyball players were on average markedly older than the other groups. Skeletal maturity was categorized as early, on-time, or late using a ±1.0-year SA–CA threshold. Menarche status was recorded as an indicator of pubertal development. Group differences were evaluated using chi-square or Fisher’s exact tests as appropriate, while differences in SA and SA–CA according to menarche status were assessed using Welch’s t-test. Results: Volleyball players were older (12.90 ± 0.95 years) than non-athletes (10.22 ± 2.40 years) and track-and-field athletes (8.47 ± 1.51 years). They also demonstrated the largest mean SA–CA difference (+1.98 ± 0.73 years). The distribution of maturity categories differed across groups (χ²(4) = 14.32, p = 0.006, Cramer’s V = 0.30). Post-menarcheal girls exhibited significantly higher skeletal age and SA–CA values compared to pre-menarcheal girls. However, the substantial age disparity between groups represents a primary confounding factor and limits interpretation of sport-specific effects. Conclusions: This study demonstrates the practical application of BAUSport™ for rapid, radiation-free skeletal age assessment in youth. Differences according to menarche status support the biological relevance of skeletal maturity assessment. However, no valid between-group sport-specific inferences can be made because the groups were not age-matched and puberty is the dominant driver of skeletal maturation. Larger, age-matched studies are required before drawing conclusions regarding sport-specific selection patterns. Full article

Objectives: The aim of this paper is to determine whether leg kinematics and the normal force generated during the stance phase of running differed between (i) long-distance runners with medial tibial stress syndrome (MTSS) or (ii) long-distance runners who were asymptomatic at baseline testing but developed MTSS compared to asymptomatic control participants. Methods: Lower-limb kinematics, normalised stance-phase forces and spatiotemporal outcome variables were compared between the limbs of MTSS symptomatic long-distance runners (n = 11) and matched asymptomatic controls (n = 11). Outcome variables were also compared between the limbs of long-distance runners who were asymptomatic at baseline but developed MTSS (n = 4) compared to asymptomatic control limbs. Results: In the case-control comparison, MTSS symptomatic participants demonstrated slower running speeds but no differences in stance-phase normal forces or kinematics compared to asymptomatic controls. In the case study, participants who developed MTSS during the study displayed substantially lower normal forces, less plantar flexion and a more vertical tibia than the asymptomatic controls. Conclusions: The slower running speeds observed among the MTSS symptomatic participants may be pain-related or reflect reduced plantar flexor propulsive capacity. The development of MTSS by Participants 1 and 2, despite lower normal forces and plantar flexion compared with asymptomatic controls, suggests that the tibial load tolerance may vary among individuals. Furthermore, the peak stance-phase force appears to have limited utility as a standalone screening tool for MTSS injury risk. Finally, further prospective research is required to investigate plantar flexor function, propulsive force capacity and the risk of MTSS development to substantiate these findings. Full article

Background: Breath-hold training (BHT) has emerged as a novel strategy to enhance metabolic efficiency and autonomic resilience in national-level athletes. This signal-generating single-case study examined physiological and neuroendocrine adaptations to an eight-week BHT program in a nationally ranked competitive swimmer. Methods: A national-level 23-year-old female freestyle sprinter (50 m best time = 26.59 s; 100 m = 60.40 s) completed three weekly BHT sessions integrated into her regular training. Pre- and post-intervention assessments included an incremental Mader cycling test with measurements of blood lactate ($\left[{\mathrm{La}}^{-}\right]$), heart rate (HR), salivary cortisol (sCort), and salivary alpha-amylase (sAA). Blood chemistry and pulmonary function, including diffusing capacity of the lung for carbon monoxide (DLCO), were also evaluated. Results: Post intervention, the athlete demonstrated reduced $\left[{\mathrm{La}}^{-}\right]$ and HR at all workloads, a 20 W increase in power at 4 mmol·L⁻¹ $\left[{\mathrm{La}}^{-}\right]$, and an elevated final workload achieved during the Mader test. Salivary stress biomarkers showed blunted responses with significant reductions in area under the curve and large effect sizes. These changes were observed under standardized pre-analytical conditions and individualized training adjustments. Conclusions: This study highlights coordinated improvements in metabolic, cardiovascular, and stress regulation mechanisms following BHT in a swimmer with verified national-level performance benchmarks. BHT, when applied in sport-specific contexts, may serve as an effective adjunct to high-performance training. Full article

Background: In this study, trunk extension strength was compared between healthy female and male participants. Methods: Overall, 115 women and 124 men underwent isometric maximal voluntary contraction (MVC) testing in an upright standing position. Upper body weight was additionally assessed. The primary outcome variables were maximal torque, upper body weight expressed as torque, and the MVC-to-upper-body-weight ratio. In view of the large sample size, interpretation of the results was based not only on statistical significance but also on clinical/practical relevance, as reflected by effect size (ES) and the relationship between the difference in mean values (DMV) and the minimal important difference (MID). Results were classified as relevant only when all three predefined criteria were met (p < 0.05, ES > 0.5, and DMV > MID). Results: Men showed significantly higher MVC values than women (241 Nm vs. 162 Nm; p < 0.0001; ES = 1.974; DMV > MID). Likewise, upper body torque was significantly greater in men than in women (115 Nm vs. 80 Nm; p < 0.0001; ES = 2.119; DMV > MID). However, after normalization for upper body torque, the between-sex difference in relative strength was no longer considered relevant (2.16 vs. 2.00; p = 0.0055; ES = 0.364; DMV < MID). Conclusions: These findings indicate that although absolute trunk extension strength differs markedly between sexes, relative strength adjusted for upper body weight is broadly comparable. Both women and men demonstrated a physiological strength reserve of approximately 100% relative to upper body weight. Full article

Background: Recreational half-marathon participation is increasing, particularly among middle-aged amateur runners, yet the interpretation of early post-race cardiac findings remains challenging in exercise-based cardiovascular health evaluation. This exploratory study assessed early post-race changes in left ventricular diastolic indices and circulating biomarkers in 20 healthy amateur runners (80% male; mean age 50.7 ± 12.3 years) after the 11th PELLA HALF MARATHON (21.1 km). Methods: Participants underwent transthoracic echocardiography and venous blood sampling within 30 days before the race and within 30 min after finishing. Diastolic assessment included the E/A ratio, tissue Doppler early diastolic myocardial velocity (e′), the E/e′ ratio, isovolumic relaxation time (IVRT), and left atrial area. Biomarkers included C-reactive protein (CRP), creatine phosphokinase (CPK), creatine kinase-MB (CK-MB), and high-sensitivity cardiac troponin I (hs-cTnI). Results: Post-race assessment showed a consistent pattern of lower early diastolic filling/relaxation indices, higher IVRT and left atrial area, and significant increases in all measured biomarkers. hs-cTnI exceeded the sex-specific 99th percentile upper reference limit in 7/20 participants (35%). Conclusions: Half-marathon completion was associated with early echocardiographic and biomarker changes in this cohort of amateur runners. These findings are consistent with acute physiological cardiac stress and may help clinicians contextualise early post-race abnormalities when advising on vigorous endurance exercise participation. However, subclinical myocardial injury cannot be excluded without serial biomarker assessment and advanced imaging, and the findings should be interpreted as exploratory because of the small convenience sample, absence of a control group, lack of hydration assessment, and single early post-race timepoint. Full article

Background: Reports on subchondral bone mechano-structure in individuals with various stages of knee osteoarthritis (KOA) are limited and often conflicting in contemporary literature. Our study aimed to assess differences in subchondral trabecular bone mechano-structure across late KOA stages in a homogenous group of patients with varus malalignment (confirmed by negative hip-knee-ankle-angle values). Methods: This retrospective cross-sectional study included micro-computed tomography scanning and Vickers micro-hardness testing of 90 bone samples (30 femoral and 60 tibial) collected from 15 adult patients with primary KOA undergoing total knee arthroplasty (TKA). The Kellgren–Lawrence grading system was used to assess the severity of KOA lesions in the included individuals, and bone samples were divided into the following groups: moderate KOA (42 samples from seven patients, age: 70 ± 7 years, females: 3/7) and end-stage KOA (48 samples from eight patients, age: 70 ± 6 years, females: 5/8). Results: Our data revealed site-specific sclerotic alterations in subchondral trabecular bone mechano-structure (thicker trabeculae, coupled with higher bone mineral content and increased bone micro-hardness) in individuals with end-stage KOA compared to moderate KOA, supporting its role in KOA pathogenesis beyond the exclusive cartilage degeneration effect. Our data also revealed that most heterogeneous subchondral trabecular mechano-structure was present in bone samples obtained from the medial part of the tibial and femoral condyle, revealing the substantial effect of mechanical loading during varus knee malalignment. Conclusions: Observed site-specific alterations in subchondral bone mechano-structure in individuals with end-stage KOA supported the role of subchondral sclerosis in primary KOA pathogenesis beyond its exclusive effect on cartilage degeneration. Full article