Sports最新文献

Monitoring the training load of elite soccer players is a common practice for clubs. However, limited information exists about the internal load experienced by elite soccer players. The heart rate (HR) exposure of 51 French elite soccer players was monitored using conductive vests incorporating ECG bands during two consecutive seasons using a three-zone intensity model. HR exposure was broken down into volume (i.e., total time in the three zones) and intensity (i.e., relative time in the three zones). The effect of playing position, as well as the period (monthly or daily), was assessed. Regarding seasonal exposure, a significant difference was observed between key periods of the season (i.e., preseason, in season, end-of-season) for both volume and intensity (p < 0.05). Noteworthily, monthly HR exposure was relatively constant across competitive period. For weekly exposure, a significant difference in HR volume and intensity was observed between matches and training sessions (p < 0.001) potentially highlighting gaps in players' readiness. Note that there were small variations in terms of HR exposure between the three first training days (p < 0.05), especially for time and relative time over 90% of maximal HR (not significant). This study not only provides insight into typical HR exposure in elite football but also questions the current training periodisation.

Background: Despite many young players showing strong potential, only a small fraction succeeds in the critical transition from youth to elite senior football. This scoping review synthesizes research on the junior-to-senior transition in men's football, identifying main topics related with barriers and facilitators in the transition.

Methods: Searches were performed in four databases (PubMed, Scopus, SPORTDiscus, and Web of Science) according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA, 2020) guidelines, using the following keywords: "football*" OR football AND talent* OR "talent identification" OR "talent development" OR expert* OR gift* AND "junior-to-senior" OR "transition career" or "athlete career transition" OR "transition phase". Original articles in English focused on the junior-to-senior process in male footballers were included.

Results: From 5307 titles, 35 studies met eligibility criteria. The most examined themes were psychosocial factors, including social support, stressors, and resilience. The reviewed studies identified organizational structure and effective club communication as facilitators and emphasized the importance of physical attributes to meet senior-level demands.

Conclusions: Overall, the junior-to-senior transition is multifaceted, shaped by psychosocial, organizational, and physical factors. Despite robust research, gaps remain; future longitudinal and interdisciplinary studies should inform evidence-based strategies for optimizing player development and retention.

Hamstrings-quadriceps (H-Q) imbalance represents a biomechanical marker of knee instability and injury risk in running. This in silico (simulation-based) study introduces a digital machine learning framework designed to estimate H-Q imbalance using biomechanical features derived entirely from synthetic running trials and conceptually mappable to inertial-sensor domains. Key biomechanical predictors included the dynamic hamstrings-to-quadriceps ratio (H:Qdyn), the knee moment limb symmetry index (LSI), and the early-stance co-contraction index (CCI), all standard indicators of muscular balance and coordination in sports medicine. A reduced musculoskeletal framework emulating flexor-extensor balance, limb symmetry, and co-contraction patterns generated 573 synthetic running trials for 160 virtual subjects across three speeds. These interpretable features trained a calibrated gradient-boosting classifier evaluated via ROC-AUC, PR-AUC, balanced accuracy, F1, and Brier score. Across all conditions, the model achieved ROC-AUC 0.933 (95% CI 0.908-0.958), balanced accuracy 0.943 (95% CI 0.924-0.962), PR-AUC 0.918 (95% CI 0.892-0.943), F1 0.940 (95% CI 0.919-0.958), and Brier 0.056 (95% CI 0.041-0.072), outperforming the logistic baseline. Dynamic H:Q ratio and knee moment symmetry were the dominant predictors, while co-contraction provided complementary biomechanical nuance. These results demonstrate that simulation-derived frameworks can reproduce IMU-relevant biomechanical variability, enabling interpretable machine learning for transparent assessment of muscular balance in sports medicine.

The present systematic review aims to provide a comprehensive synthesis of evidence and practices regarding sustainable career transitions in elite sport. Following PRISMA guidelines, an extensive literature search was conducted in SPORTDiscus (EBSCOhost), PsycINFO, Scopus, Web of Science, and Google Scholar databases, resulting in 117 manuscripts, published from January 2015 to May 2025, and meeting the defined inclusion criteria. The review focused on mental health, dual-career pathways, transition readiness, and identity-related issues among elite athletes, Olympians, and Paralympians. Methodologies included qualitative, quantitative, and mixed-methods designs, with multisport and mixed-gender samples prevailing. The most commonly used instruments were semi-structured interviews and surveys. The main findings highlighted the centrality of mental health support, the role of dual-career planning, and the importance of proactive identity negotiation. Despite growing research interest, significant gaps persist in access to psychological support, structured transition planning, and dual-career strategies, with notable inconsistencies across countries and sports. The review emphasizes the necessity for integrated, multidimensional guidance, culturally sensitive psychological services, and flexible educational pathways to promote athlete well-being and sustainable post-sport careers. These insights are intended to inform the implementation of the ERASMUS+ funded PORTAL project, supporting evidence-based interventions and the development of resources such as an online platform and Real-Life Transition Officers to enhance the transition experiences of elite athletes.

This retrospective, non-interventional study investigated the impact of a forced training interruption, such as the COVID-19 nationwide lockdown, on the physical efficiency, performance, and technical-agility skills of prepubertal soccer players by comparing pre- and post-interruption cohorts within the same youth academy and at the same chronological age. Anonymised data collected across multiple competitive seasons included anthropometric measures and motor performance tests: Standing Long Jump, Shuttle Run, Shuttle Dribble, and Mini Cooper. Between-group differences were analysed using Mann-Whitney U tests, with p < 0.05 as the level of significance. The post-training interruption cohort showed significantly higher values in the Standing Long Jump (+11.2%, p < 0.001) and the Shuttle Run (+8.0%, p = 0.011), indicating improved explosive power and agility-speed. Conversely, performance on the Shuttle Dribble test declined by 13.4% (p < 0.001), while Mini Cooper results and BMI did not differ significantly. These findings suggest that modifications to compulsory training and children's natural adaptability may have enhanced physical abilities, whereas the lack of contextual and interactive practice negatively affected technical-agility skills. Coaches should incorporate alternative workouts to maintain motor performance and emphasise ball-related and decision-making drills within ecological and dynamic environments to maximise developmental outcomes. This study offers new insights into the adaptive responses of young athletes and provides practical lessons for future youth soccer development, particularly during periods of forced training interruption.

Background: Gender differences in anti-doping rule violations (ADRVs) have been noted in international research, yet systematic analyses are rare. This study addresses that gap by providing the first comprehensive evaluation of the doping prevalence by gender in Serbia.

Methods: A 19-year retrospective quantitative analysis was conducted on data collected by the Anti-Doping Agency of Serbia (ADAS) between 2006 and 2024. In total, 14,919 doping controls were performed, including 10,912 (73.11%) on male athletes and 4007 (26.89%) on female athletes.

Results: Across this period, 146 ADRVs were identified, with a clear gender imbalance: 128 (87.32%) cases involved male athletes and 18 (12.68%) female athletes. A Chi-Square test confirmed a significant association between gender and ADRVs, χ²(1, N = 14,919) = 15.11, p < 0.001, indicating that male athletes were more likely to violate anti-doping rules. Substance profiles also differed: anabolic agents (S1) dominated overall, while stimulants (S6) and cannabinoids (S8) were more frequent in males, and diuretics (S5) and hormone modulators (S4) in females.

Conclusions: These findings reveal a pronounced gender disparity in doping behavior and substance choice, providing a foundation for further research and emphasizing the need for gender-sensitive anti-doping education and policy.

This case report describes the acceleration of an Olympic decathlete's return to competition induced via high-frequency Blood Flow Restriction (BFR) training. BFR has gained popularity as an innovative rehabilitation method for promoting muscle repair and adaptation through anabolic and regenerative pathways when high mechanical loading is not possible. A 26-year-old elite decathlete with nine years of international experience sustained a Grade 2b strain of the semimembranosus and semitendinosus (a 9 mm central tendon tear) during a hurdle sprint. The injury was confirmed via MRI two days post-injury. Grade 2b hamstring injuries with intramuscular tendon involvement commonly require up to 4 weeks of rehabilitation before full training can be resumed. With the athlete due to complete in an Olympic Games competition 17 days post-injury, an intensive BFR-assisted rehabilitation program was initiated. Over 12 consecutive days, the athlete completed 3-6 BFR sessions per day (20-30 min each) at 50% limb occlusion pressure, along with physiotherapy and pain-limited functional testing. BFR was applied passively for recovery, during conditioning, and in low-load strength sessions. By day 12, sprint velocity reached 95% maximum, and the athlete successfully completed the decathlon, with no adverse effects or reinjury. This case illustrates how high-frequency BFR-assisted rehabilitation may facilitate accelerated recovery from a hamstring injury, enabling an effective return to elite competition within condensed timelines.

The use of chemically assisted performance enhancement (CAPE) substances has become a prominent trend in today's competitive societies. Although evidence suggests that CAPE behaviors across different life domains share common characteristics, no consistent theoretical framework exists for understanding the decision to engage in such behaviors. The aim of the present study was to examine a unified conceptualization of CAPE behaviors in four life domains. A total of 254 participants (64 competitive athletes, 40 recreational exercisers, 67 students, and 83 professionals) completed a survey assessing distal and proximal associations of CAPE behaviors (adapted for each domain). Path analysis used to evaluate the proposed model demonstrated an adequate fit. Results indicated that proximal associations of intentions (i.e., attitudes, norms, and situational temptation) were predicted by distal variables (i.e., social norms and cultural values). Intentions to engage in CAPE behaviors were predicted by attitudes and situational temptation. Goal commitment predicted only the mean of working, studying, or training. Finally, the mean of supplement use was predicted by norms. These findings provide preliminary evidence for a conceptual framework to understand CAPE behaviors across life domains, which may serve as a basis for designing intervention programs aimed at helping individuals make informed decisions about CAPE.

Pull-ups are a widely recognized exercise for training and assessing upper-body strength and muscular endurance, requiring coordinated activation of the latissimus dorsi, biceps brachii, forearm flexors, and core stabilizers. However, many individuals experience difficulty performing pull-ups due to inadequate grip strength or core stability. This study aimed to investigate the comparative effects of forearm-specific and core-specific training, combined with standardized pull-up routines, on upper-body performance indicators in physically inactive male students. Thirty participants (age = 21 ± 1.58 years) were randomly assigned to three groups (n = 10): pull-up plus interval training (PIT), pull-up plus forearm training (PFT), and pull-up plus core training (PCT). All groups performed identical pull-up-based programs for eight weeks, differing only in the supplemental exercises. Before and after the intervention, participants were tested for maximum pull-up repetitions, grip strength (both hands), and dead-hanging time. Significant improvements were found in all variables (p ≤ 0.009), with group differences in pull-up repetitions (p < 0.001) and right-hand grip strength (p = 0.004). The PFT group achieved the greatest gains, with a 222.5% increase in repetitions, 12% and 14.0% increases in right- and left-hand grip strength, and a 55.3% increase in hanging time. The PCT group showed moderate progress, while PIT yielded the smallest improvement. Forearm-specific training proved the most effective strategy for enhancing pull-up performance, grip strength, and endurance.

Jumping exercises are widely applied in sport performance and conditioning due to their crucial role in enhancing neuromuscular function and lower-limb power. Acute effects related to contractile properties measured by tensiomyography (TMG) remain insufficiently explored. This study aimed to examine the acute effects of two jump types-bilateral countermovement jumps (CMJs) and stiffness jumps (STs)-on the contractile properties of the vastus medialis (VM) and medial gastrocnemius (GM) muscles. Twenty-nine kinesiology students (fourteen males, fifteen females; age 19.4 ± 0.7 years) performed CMJ and ST protocols in a randomized order. Muscle contractile characteristics were measured before and immediately after each protocol and analyzed using a mixed-model repeated-measures ANOVA. Significant pre-post changes were found in both muscles. In the VM, contraction (Tc) and delay (Td) times decreased (p < 0.01), indicating faster responses, whereas relaxation time (Tr) increased and sustain time (Ts) decreased (p < 0.05), suggesting temporary fatigue. Maximal displacement (Dm) increased (p < 0.01), indicating reduced stiffness. In contrast, the GM showed greater responsiveness after stiffness jumps, characterized by shorter Tc and Td (p < 0.01), and reduced endurance after CMJs. These findings highlight muscle specific neuromuscular adaptations and provide practical insights for optimizing warm-up, training, and rehabilitation protocols through targeted jump selection.