Biology of Sport最新文献

The aims of the present study were to: (i) quantify accelerations and decelerations of soccer players during match-play across two consecutive seasons from the English Premier League (EPL) and Ligue 1 (L1); and (ii) compare any positional differences between the two leagues. Fifty-eight male professional soccer players were monitored during all league matches (n = 144) across seasons 2020/21 and 2021/22. The absolute number of accelerations (> +3 m/s^-2) and decelerations (< -3 m/s^-2) and accelerations and decelerations per minute were examined. The relative number of accelerations and decelerations across all positions was higher with moderate effect sizes in the EPL when compared to L1 (p < 0.001, for both). Significant differences were observed in accelerations and decelerations across all playing positions (p < 0.001 and p = 0.001 respectively, with moderate to very large effect sizes), except for centre forwards (CF) (accelerations p = 0.40; ES = 0.16; decelerations p = 0.97; ES = 0.01). This study provides valuable insights into the positional acceleration and deceleration differences in the EPL and L1, which should be considered in match running performance evaluations. While confirming higher accelerations and decelerations in the EPL, the unique case of CF challenges current evidence, emphasising the need for a more granular understanding of the positional demands of explosive actions incorporating accelerations and decelerations in elite soccer.

The aims of this study were to: compare training loads between the English Premier League (EPL) and English Championship League (ECL) and examine differences between playing positions. Forty-six 1^st team players from the same club participated in the study. GPS metrics were obtained during all EPL and ECL training sessions across four consecutive seasons, 2019-20 to 2022-23. The study team was promoted from the ECL at the end of season 2020-21. There was a significant interaction effect between position and league for all GPS metrics (p < 0.001; η² = 0.001-0.003), except for relative high-speed running (HSR) distance, sprint distance, and sprint efforts (p > 0.05). A significant main effect for league for all GPS metrics (p < 0.001; η² = 0.001-0.009) was found, with EPL training sessions resulting in greater total distance per minute, HSR distance per minute, high metabolic load distance (HMLD) per minute, number of HML efforts, accelerations, and decelerations per minute compared to training in the ECL (p < 0.001; d = 0.061-0.224). For position, a significant main effect for all GPS metrics (p < 0.001; η² = 0.001-0.005) was observed. Centre midfielders covered more distance per minute than all other positions (p < 0.001, d = 0.040-0.167). In conclusion, higher training values in the EPL were evident, except for centre forwards, providing some guidance on the differing positional physical demands that may support coaches and practitioners to design position-specific drills incorporating physical and technical/tactical strategies.

This study aimed to examine the differences in physical performance when winning and losing in UEFA Champions League (UCL) matches. Data were collected using an optical tracking system from all UCL matches (n = 125) in the 2022/23 season. A linear mixed model was used to examine the differences in physical performance in won and lost matches while controlling for match location, team formation, opponent quality, playing time, red cards, and between-player, -team, and -match variations. The results indicated that (i) wingers and forwards covered ~ 20% greater high-intensity running distance in won compared to lost matches (Cohen's d (d) = 0.76 and 0.96, respectively), (ii) central defenders and fullbacks covered ~ 15% greater high-intensity running distance in lost compared to won matches (d = 0.59 and 0.32, respectively), (iii) offensive midfielders achieved ~ 2% greater low-intensity running distance (d = 0.59) while defensive midfielders performed ~ 2% greater total distance (d = 0.81) in won compared to lost matches. These findings suggest that winning was physically more demanding for offensive players but losing was more demanding for defensive players, while midfield players' physical demands were similar irrespective of winning and losing. Soccer coaches should consider implementing an extended period of recovery for offensive and defensive players following won and lost matches, respectively.

Despite the development of various motor learning models over many decades, the question of which model is most effective under which conditions to optimize the acquisition of skills remains a heated and recurring debate. This is particularly important in connection with learning sports movements with a high strength component. This study aims to examine the acute effects of various motor learning models on technical efficiency and force production during the Olympic snatch movement. In a within-subject design, sixteen highly active male participants (mean age: 23.13 ± 2.09 years), who were absolute beginners regarding the learning task, engaged in randomized snatch learning bouts, consisting of 36 trials across different learning models: differential learning (DL), contextual interference (serial, sCI; and blocked, bCI), and repetitive learning (RL). Kinematic and kinetic data were collected from three snatch trials executed following each learning bout. Discrete data from the most commonly monitored biomechanical parameters in Olympic weightlifting were analyzed using inferential statistics to identify differences between learning models. The statistical analysis revealed no significant differences between the learning models across all tested parameters, with p-values ranging from 0.236 to 0.99. However, it was observed that only the bouts with an exercise sequence following the DL model resulted in an average antero-posterior displacement of the barbell that matched the optimal displacement. This was characterized by a mean positive displacement towards the lifter during the pulling phases, a negative displacement away from the lifter in the turnover phase, and a return to positive displacement in the catch phase. These findings indicate the limited acute impact of the exercise sequences based on the three motor learning models on Olympic snatch technical efficiency in beginners, yet they hint at a possible slight advantage for the DL model. Coaches might therefore consider incorporating the DL model to potentially enhance technical efficiency, especially during the early stages of skill acquisition. Future research, involving even bigger amounts of exercise noise, longer learning periods, or a greater number of total learning trials and sessions, is essential to verify the potential advantages of the DL model for weightlifting technical efficiency.

The purpose of this study was twofold: to analyse physical performance fluctuations throughout match play in women's handball; and to investigate whether physical performance fluctuations are affected by contextual factors (i.e., level of the opponent and playing positions). Twenty-two female players from the Spanish 2^nd Division were monitored across 13 matches. Each match was divided into 5 min fixed phases. Total distance (TD), high-speed running (HSR) and PlayerLoad (PL) were collected using a local positioning system. The highest values of TD, HSR and PL were registered during the first 5 min phase of the match (p < 0.05, moderate-large effects), while the lowest values of TD and PL were registered in the last phase of the first half and for HSR in the last phase of the match (p < 0.001, large effects). Regarding level of the opponent, low-level teams elicited higher TD in the first 10 min of the match (p < 0.05, moderate effects). Conversely, matches involving high-level teams registered more TD and PL in the last phase of the match (p < 0.05, moderate effects). In relation to playing positions, wings showed the highest physical performance in all 5 min phases of the match, whereas the pivots showed the lowest physical performance. In the present study the physical performance decreased throughout the match and the fluctuations were strongly affected by the level of the opponent and playing positions. Therefore, handball coaches should incorporate strategies to mitigate fatigue within and between halves.

Quantifying competition load with kinematic variables from inertial devices provides critical insights into player performance, a practice well adopted especially in team sports. This study aimed to analyse load variables in elite padel players, distinguishing between match winners and losers. Data were collected from 83 players across 23 professional circuit matches. The results highlighted specific load metrics such as distance covered, accelerations and decelerations per hour, peak speeds, and an acceleration profile per distance covered, revealing that winners exhibited significantly higher mobility than losers. Specifically, match winners travelled a greater distance per hour than match losers (Mdn_Winners = 2518; Mdn_Losers = 2339 m; p = 0.02; r = 0.25) and performed a greater number of accelerations per hour (Mdn_Winners = 415; Mdn_Losers = 382; p = 0.04; r = 0.22). These findings introduce novel data to padel, promising to refine training adjustments and offer an objective performance evaluation in both training and competitive contexts. The study's outcomes emphasize the role of mobility in winning matches, suggesting that higher movement and acceleration rates are advantageous. This research fills a gap in padel literature, providing a foundation for future investigations into training and performance optimization strategies.

This study aimed to characterize match peak speeds, during a 20-second time window (10 seconds immediately before and after the match peak speed), in soccer matches. Twenty elite soccer players were monitored with global navigation satellite system (GNSS) devices during six soccer matches from the Brazilian first division. After identifying the peak speed, individual speeds within 10 seconds before and 10 seconds after were collected at each 0.1-second interval (10 Hz). Intra-individual speed differences were assessed at every second of the selected window using paired mean differences (with effect sizes and 95% confidence intervals). Match peak speeds ranged from 29.11 km/h to 31.64 km/h. Speeds registered 10 seconds before and 10 seconds after the match peak speed ranged from 5.11 km/h to 9.21 km/h and 6.90 km/h to 7.65 km/h, respectively. Speed increased moderately (effect size [95% confidence interval]: 0.68 [0.64, 0.73]) 4 seconds before the match peak speed and decreased moderately (effect size [95% confidence interval]: -0.73 [-0.78, -0.68]) 3 seconds after the maximal effort. Match peak speeds were achieved from flying starts, differing from the current sprint test procedures. Players needed to accelerate from speeds of approximately 10 km/h to reach their peak speed. After the match peak speed, players decelerated faster than they accelerated but without reaching a complete stop. Nevertheless, preparing players for intense decelerations should not be disregard. Players can benefit from field tests and training sessions that provide similarities to what occurs during competition, and accelerations should also be considered when referring to peak speeds.

The main objective of this study was to identify the game-related statistics determining the sports results in volleyball between 2004 and 2016. In the study, the matches of six men's and six women's national volleyball teams competing in the most prestigious international events were analysed. It should be emphasised that the data included in the analysis concerned the games played during the World Championship, Olympic Games, World Cup and the World Grand Champions Cup. The obtained results revealed that in the women's group the variables number of successful attacks (p < 0.025) and number of blocking points (p < 0.044) were the fundamental factors determining success in volleyball at the elite level in the analysed period. Considering the main goal of the study, in men's teams the number of blocking points (p < 0.007) and number of serve points (p < 0.008) were the main factors.

This systematic literature review (SLR) aimed to comprehensively synthesize existing studies that have reported on TMG-derived parameters of lower extremities in soccer players. The PubMed, Web of Science, and EBSCOHost (including MEDLINE, SPORTDiscuss, ERIC, DOAJ, and SCOPUS) databases were searched from inception to the 31^st of August, 2023. Reports were eligible if they satisfied the following criteria: recruited active soccer players, with no restriction on race, sex, age, level of expertise, or health status; studies utilizing TMG for measuring muscle contractile properties. In total, 25 published journal articles from 22 original studies were included in the current review, encompassing a total of 1224 participants (4% females). The analysis considered various muscles, with the biceps femoris (BF), rectus femoris (RF), vastus lateralis (VL), vastus medialis (VM), semitendinosus (ST), gastrocnemius lateralis (GL), and gastrocnemius medialis (GM) being investigated. Significant variations were observed in TMG parameters across different muscles, age categories, and levels of play. The quality of evidence varied from low to moderate for all analyses. The meta-regression analysis indicated that age moderated several TMG-derived parameters in lower limb muscles including BF Vc, RF Td and Vc, ST Dm and sustain time, VL Dm, Tc, Td and relaxation time (Tr), and VM Tc, Td and Tr, respectively. In conclusion, the current review illuminated the multifaceted applications of TMG in assessing lower extremity muscles in soccer players. Beyond evaluating muscle contractile properties in various superficial muscles of the lower limbs in soccer players, TMG-derived parameters may serve as potentially valuable markers in identifying neuromuscular risk factors for anterior cruciate ligament injuries and predicting hamstring-related injuries.

Vitamin D₃ exhibits strong antioxidant properties. However, its effect on oxidative stress after strenuous endurance exercise remains unclear. Therefore, we investigated the effects of vitamin D₃ supplementation on strenuous endurance-exercise-induced oxidative stress. In this study, 26 male participants consumed vitamin D₃ (5,000 IUs of vitamin D₃ daily for 4 weeks) or placebo. After four weeks, all participants performed strenuous endurance exercise at 65% of $\dot{\text{V}}$ O_2max. Blood samples were collected before and after four weeks of supplementation to determine the participants' serum 25(OH)D concentration. Additionally, venous blood samples were collected before, immediately after, two hours after, and 24 hours after the strenuous endurance exercise test to analyze markers of oxidative damage (thiobarbituric acid reactive substances, and protein carbonylation) and antioxidant enzyme activity (catalase, glutathione peroxidase, and superoxide dismutase). After four weeks of vitamin D₃ supplementation, the concentrations of protein carbonylation and superoxide dismutase at post-0-h, post-2-h, and post-24-h were significantly higher in the placebo group than in the vitamin D₃ group (all p < 0.05); the concentration of thiobarbituric acid reactive substances was significantly higher in the placebo group than in the vitamin D₃ group at post-24-h (p < 0.05); and the concentration of catalase was significantly higher in the placebo group than in the vitamin D₃ group at post-0-h (p < 0.05). Our results indicated that four weeks of 5,000-IU vitamin D₃ supplementation (oil form) effectively increased the participants' serum 25(OH)D concentration and mitigated the accumulation of strenuous-endurance-exercise-induced markers of oxidative stress (e.g., thiobarbituric acid reactive substances and protein carbonylation).