Peter Bartik

Purpose: This study aimed to investigate the prevalence of W-sitting, gait, and foot analysis in preschool and school-age participants. Methods: A cohort study was conducted, including healthy participants without any pathology or other diagnoses. Foot disposition was determined using the Foot Posture Index (FPI-6), and gait patterns were analysed using the Zebris FDM platform. The study was conducted at the Gait Laboratory of King Abdullah Specialised Children’s Hospital and Prince Sultan University in Riyadh, Saudi Arabia. A total of 190 participants were included, ranging in age from 12 to 109 months. The preschool-aged children (12–60 months) comprised 168 participants (88%), while the school-aged children (61–109 months) comprised 22 participants (12%). Results: The preschool group had a female majority (92, 55%), while males accounted for 76 participants (45%). W-sitting was observed in both groups, with 61 preschool participants (36%) and eight school-aged participants (36%) preferring this posture. Gait analysis revealed patterns specific to preschool children aged 12–60 months, indicating an increased pronation on the left foot. However, the overall risk of developing foot pronation or supination deformities in Saudi participants was low, though not negligible. Conclusions: W-sitting may impact foot posture and gait patterns. Early assessment of foot posture and gait during the paediatric age is recommended to minimise the risk of complications or deformities that may affect a child’s development.

Purpose This study aimed to investigate the effect of gender on balance performance among physically active young adults by analyzing anterior, posterior, and central stability tendencies. While balance is a multifactorial ability influenced by sensory integration and neuromuscular coordination, evidence regarding gender-specific postural strategies remains inconsistent. Methods Fifty-two healthy participants (26 males and 26 females, aged 18–25 years) who engaged in regular exercise were assessed using the Sigma Balance System (CosmoGamma, Italy). Balance performance was evaluated through a dynamic limit of stability test, and the percentage of time spent in anterior, posterior, and central zones was calculated. Independent samples t-tests and Welch’s t-tests were applied depending on variance homogeneity, with a significance level of p<.05. Results No significant gender differences were observed in anterior or posterior sway tendencies (p>.05). However, females demonstrated significantly higher centering performance than males (p=.0246, R 2 =.1477), indicating a moderate effect size. These findings suggest that although the general mechanisms of postural control are similar across genders, central stability strategies differ, potentially reflecting distinct neuromotor adaptations. Conclusion The results highlight that females employ more precise neuromuscular control to maintain balance within the central stability zone. This advantage may offer performance benefits in sports requiring static or semi-dynamic postures, while emphasizing the need for gender-specific balance training and rehabilitation approaches. Overall, the study contributes to understanding how gender-related biomechanical and neuromotor factors shape postural control among physically active young adults.

Swimming performance in youth athletes is influenced by a complex interplay of physical, motor, and physiological factors. Among competitive swimming strok

Background and Objectives: This study aimed to compare acute changes in body composition parameters following marathon (42.195 km) and ultramarathon (61 km) runs in trained male athletes, with particular focus on hydration dynamics and metabolic stress. Materials and Methods: Sixteen male amateur endurance runners were assigned to two groups: marathon (n = 8) and ultramarathon (n = 8). Body composition was assessed at three time points pre-race, immediately post-race, and 24 h post-race using bioelectrical impedance analysis. Measurements included body weight (BW), body mass index (BMI), total body water (TBW), total body fat (TBF), lean body mass (LBM), right arm fat (RAF), left arm fat (LAF), right leg fat (RLF), left leg fat (LLF), and torso fat (TF). Results: Both groups exhibited significant reductions in BW and BMI post-race (p < 0.05), with more pronounced changes observed in the ultramarathon group. Partial restoration of these metrics occurred within 24 h, primarily due to glycogen resynthesis and fluid retention. TBW remained stable immediately post-race but increased notably during recovery, particularly in ultramarathon runners, suggesting more effective hydration responses. Muscle and fat-free mass changes were minimal but more favorable in the ultramarathon group. Both total and regional fat percentages declined significantly post-race in both groups, with ultramarathon runners showing greater reductions. Conclusions: Endurance running induces short-term but substantial alterations in body composition, with ultramarathon participation eliciting more pronounced metabolic and fluid balance responses. These findings highlight the importance of race-specific nutritional and hydration strategies tailored to event type and duration.

Background: Percussion massage (PM) using massage guns has become popular for enhancing flexibility, muscle performance, and recovery, but evidence on its efficacy is mixed. Foam rolling (FR) is another standard modality with similar claims. This study aimed to compare the acute effects of PM and FR on hamstring flexibility, specific muscle performance types (reactive and explosive strength), and muscle fatigue. Methods: A randomized, controlled crossover design was employed with 18 physically active university students. Participants underwent three conditions: PM with Theragun, foam rolling, and a no-activation control (WA), each separated by a 4–5 day washout. Flexibility was assessed via the Active Knee Extension (AKE) test. Muscle performance was evaluated using a Single-Leg Reactive Strength Test (SLRST), a leg press explosive strength test, and a 30-s side hop test to assess endurance and fatigue. Statistical analyses included repeated measures ANOVA and non-parametric tests where appropriate. Results: PM significantly improved hamstring flexibility, demonstrated by lower AKE angles compared to FR and WA ( p < 0.01), while no significant flexibility differences were found between FR and WA. No significant effects of any intervention were observed on reactive strength index, leg press power, or hop test performance. The reliability of the measurements was high (ICC > 0.84). Conclusions: PM provides an immediate enhancement in hamstring flexibility superior to FR and no treatment, but none of the interventions acutely improve muscle reactive/explosive strength or endurance. These findings suggest that PM may be an effective pre-activity tool for improving flexibility. However, it should not be relied upon as an acute performance enhancer for physically active individuals. Further research on long-term and varied protocol effects is recommended.

Elite-level athletes develop distinct performance profiles shaped by training regimens tailored to the specific physical and physiological demands of their respective sports. The nature of the sport, training methods, and game dynamics directly influence the development of strength, power, speed, and anthropometric characteristics. In team sports, comparative evaluations of these attributes are critical for accurate performance analysis and the design of sport-specific and individualized training pro-grams. This study aimed to compare the anthropometric characteristics, strength, ex-plosive power, and speed parameters of elite male football and handball players. A total of 44 athletes (22 football players and 22 handball players) participated in this cross-sectional comparative study. Anthropometric data included height (cm), body weight (kg), and body mass index (BMI, kg/m²). Performance assessments comprised leg strength (kg), handgrip strength (kg), vertical jump height (cm), 30-meter sprint time (s), and peak power output (W). Independent samples t-tests revealed statistically significant differences between football and handball players in age (p = .004), height (p = .005), leg strength (p = .007), and handgrip strength (p < .001). No significant differences were found in other performance variables (p > .05). The findings indicate that elite football and handball players exhibit sport-specific anthropometric and performance profiles. Football players showed greater lower-body strength, while hand-ball players had superior upper-body strength and greater stature. These differences underscore the importance of developing training protocols and talent identification strategies that reflect the unique demands of each sport. Coaches are encouraged to utilize sport-relevant performance tests and interpret results contextually to optimize athlete development and specialization.

Background Among the key factors for cross-country skier training are high altitude training and strength in double-polling, because has recently been used not only for long-distance races but also for World cup. This study aimed to identify the effects of artificially induced high altitude on acute performance changes during aerobic (AE) and anaerobic (ANE) threshold exercises. Sport-specific tests simulating double-poling cross-country skiing were performed. Methods Eleven (8 ♂ and 3 ♀) highly trained cross-country skiers (age 19±2.81, BMI 21.9±2.1) performed a stress test to determine individual AE and ANE levels and AE and ANE intensity tests at low (500 m ASL) and artificially induced high (2000 m ASL) altitudes. The altitude was simulated using the hypoxic generator HYP-100™. For double-poling, the ergometer SkiErg ® was used in the standing position. Heart rate (HR) and lactate concentration (LC) in the capillary blood were monitored. Results For the AE and ANE loads, the average HR values at an artificially induced high altitude were 3–5% higher than those at a low altitude. The differences were significant, both statistically (p0.05) nor substantively significant. Conclusions Not-adapted youth elite cross-country skiers have higher HR at artificially induced high altitudes (2000 m ASL) during the test on SkiErg ® compare to the same load in lowland (500 m ASL). The absence of alterations in the average LC confirms that it is more appropriate to monitor the HR for altitude acute effect assessment and employ LC only for verification. For the management of endurance sports training at high altitude our research confirmed that exercise must respect the principles of acclimatization processes.

Background The key factors for cross-country skier training are high-altitude acclimatization and strength in double-polling. This study aimed to identify the effects of artificially induced high altitude on acute performance changes during aerobic (AE) and anaerobic (ANE) threshold exercises. Sport-specific tests simulating double-poling cross-country skiing were performed. Methods Eleven (8 ♂ and 3 ♀) highly trained cross-country skiers (age 19±2.81, BMI 21.9±2.1) performed a stress test to determine individual AE and ANE levels and AE and ANE intensity tests at low (500m ASL) and artificially induced high (2000m ASL) altitudes. The altitude was simulated using the hypoxic generator HYP-100™. For double-poling, the ergometer SkiErg® was used in the standing position. Heart rate (HR) and lactate concentration (LC) in the capillary blood were monitored. Results For the AE and ANE loads, the average HR values at an artificially induced high altitude were 3–5% higher than those at a low altitude. The differences were significant, both statistically (p0.05) nor substantively significant. Conclusions Not-adapted youth elite cross-country skiers have higher HR at artificially induced high altitudes than for the same load in lowlands. The absence of alterations in the average LC confirms that it is more appropriate to monitor the HR for altitude acute effect assessment and employ LC only for verification.

Background: Football demands both aerobic and anaerobic capacities due to its dynamic movements, which include jumps, directional changes, ball control, and sprints. The Nordic hamstring exercise (NHE) enhances eccentric strength, which is crucial for high-intensity movements. However, the relationship between Nordic breaking point angle (NHEbpa), which is associated with eccentric hamstring peak torque during Nordic hamstring exercise, and sprint, countermovement jump (CMJ), and change of direction (COD) speed in soccer players has not been sufficiently investigated. Objective: This analysis examines the relationship between the Nordic breaking point angle and critical performance indicators—sprint speed, COD ability, and vertical jump—in football players. Methods: Fifty-eight male soccer players volunteered for the study. Assessments included anthropometric measurements, CMJ tests, 10-20-30 m sprint tests, and COD (zig-zag) tests. NHEbpa was measured using motion analysis software. Correlation analysis was used to determine the relationship between variables. A multiple linear regression analysis was conducted to evaluate the individual effects of the sprint, CMJ, and COD performances on NHEbpa, with data analyzed using JASP 0.18. Results: Correlation analysis showed strong positive correlations between NHEbpa and sprint performances (r = 0.633 to 0.666), moderate negative correlation between NHEbpa and CMJ (r = −0.406), and moderate positive correlation between NHEbpa and COD (r = 0.580). Regression analysis results were used to analyze the independent coefficients of multiple variables more comprehensively, revealing significant predictors for performance: 20-m sprint (β = 24.166, p = 0.030), 10-m sprint (β = 22.564, p = 0.047), 30-m sprint (β = 10.677, p = 0.027), and CMJ (β = 4.974, p = 0.034). Conversely, COD performance (β = −0.154, p = 0.470) did not demonstrate a significant effect. Conclusions: The study identified significant relationships between NHEbpa and sprint/CMJ performances (p < 0.05), while no meaningful effect was observed for COD speed (p > 0.05). These findings highlight the importance of eccentric strength in sprint performance, suggesting that other factors may play a more prominent role in COD. Incorporating eccentric-focused training, particularly through Nordic exercises, is recommended to enhance sprint performance and hamstring strength, which are essential for football players.

Aim: This study evaluated the effects of plyometric training with different set configurations on sprint speed, change of direction (COD), jump performance, and perceived exertion in youth football players. Method: Twenty-four U-19 players were randomized into three groups: Cluster Set (CLS, n = 8), Traditional Set (TRD, n = 8), and Control (CON, n = 8). CLS performed 8–10 sets of 2–3 repetitions, while TRD completed 2–3 sets of 8–10 repetitions in an 8-week plyometric program (2 sessions/week). The CON group did not train. Performance measures included 10 m, 20 m, and 30 m sprints, COD, Counter Movement Jump (CMJ), Reactive Strength Index (RSI), and Rate of Perceived Exertion (RPE). A repeated measures ANOVA analyzed group*time interactions. Results: Significant improvements were observed in CLS and TRD groups for sprints (10 m: f = 21.44; 20 m: f = 19.40; 30 m: f = 49.56; p < 0.001), COD (f = 14.66; p < 0.001), CMJ (f = 51.50; p < 0.001), and RSI (f = 24.91; p < 0.001). No changes occurred in CON (p > 0.05). Conclusions: CLS and TRD plyometric training improved sprint speed, COD, and jump performance, with CLS showing slightly superior results and better fatigue management.