European journal of sport science最新文献

This study investigated the associations between ovarian hormones, symptoms, sleep characteristics and nocturnal physiology in female athletes. Twenty-four National Rugby League Indigenous Women's Academy athletes (naturally cycling: n = 11 and mean age: 21 ± 3 years; hormonal contraception: n = 13 and mean age: 22 ± 3 years) completed a 5-week training camp. During the camp, oestradiol and progesterone concentrations were analysed at three timepoints according to naturally cycling and hormonal contraception groups. Symptoms and subjective sleep were measured daily. Athletes were instructed to wear an Oura ring throughout the camp for sleep and nocturnal heart rate (HR) and HR variability (HRV) measures. Statistical analyses included linear mixed models and Pearson's correlations. Neither objective (Oura ring) nor subjective (survey) sleep characteristics were associated with oestradiol or progesterone concentrations. In the naturally cycling group, a higher number of total symptoms were associated with a longer sleep onset latency (r = 0.88, 95% CI [0.60, 0.97]) and increased light sleep (r = 0.75, 95% CI [0.28, 0.93]). Higher oestradiol concentrations were significantly associated with fewer symptoms (estimate ± SE: −0.007 ± 0.002 symptoms, p = 0.003). Luteal days were associated with higher average nocturnal HR and lower HRV than follicular menstrual cycle days (estimate ± SE: 4 ± 0.57 bpm, p < 0.001; estimate ± SE: −7 ± 2.13 ms, p < 0.001, respectively). Negligible to moderate correlations were observed between sleep and total symptoms experienced by athletes using hormonal contraception. In conclusion, sleep measures were not significantly associated with ovarian hormone concentrations. A higher number of total symptoms were associated with sleep disturbance in naturally cycling athletes. To optimise sleep, female athletes may benefit from monitoring and managing menstrual cycle symptoms.

This study investigated the effects of high-intensity interval training (HIIT) with different work-to-rest ratios during the same training duration on the specific physical fitness of Chinese adolescent taekwondo athletes (N = 30, 16–20 years, 18 males and 12 females, and provincial champion/runner-up or national top 6). Athletes were randomly allocated to HIIT-20S (20 s work: 10 s rest), HIIT-30S (30 s work: 10 s rest), and a control group (2 min actual combat competitive: 1 min rest). An 8-week intervention (24 sessions, 30 min/session). Specific physical fitness was assessed using the progressive specific taekwondo test, frequency speed of kick test, 10-s high roundhouse kick test, 60-s double chop kick test, heart rate recovery (HRR), 1 repetition maximum (1-RM) squat test, and improved Illinois agility test. Statistical significance was defined as p < 0.05. Compared with the HIIT-20S (1.96%) and control (0.47%) groups, the HIIT-30S group demonstrated a significantly greater improvement in VO2peak (4.72%). In the FSKT10S test, the HIIT-20S group performed better than the HIIT-30S group (2.24% vs. 1.34%), whereas the HIIT-30S group showed higher gains in FSKTtotal (5.09% vs. 2%) and a steeper decline in KDI (−21.7% vs. −12.1%). Similarly, the HIIT-20S group outperformed the HIIT-30S group in the 10S-HRK test (3.62% vs. 0.91%), whereas the HIIT-30S group outperformed the 60S-DCK test (3.45% vs. 1.91%). Improvements in agility favored the HIIT-20S group (−8.26% vs. HIIT-30S: −4.01%; control: −0.85%). Both HIIT groups showed enhanced heart rate recovery (HIIT-30S, 2.74% and HIIT-20S, 2.57%), although no significant differences were observed in lower limb maximal strength. These findings confirm the specificity of the work-to-rest ratio: HIIT-30S effectively enhances cardiorespiratory endurance and repeated kicking endurance, whereas HIIT-20S appears to be more beneficial for optimizing explosive strength, agility, kick speed, and frequency.

The purpose of this study was to evaluate the evolution of jump and sprint force-production capacities with maturation in young soccer players. One hundred sixteen young elite male soccer players aged 11–17 years were assigned to six different groups according to their maturity status. The force–velocity (F–V) profiles in jumping and sprinting performances were compared among groups. The results show a significant, progressive, and linear improvement in the majority of F–V profile determinants of jumping and sprinting performances in parallel with maturation. When comparisons were carried out between consecutive groups, significant differences between PHV−1 and PHV groups in H_max (p < 0.05), H₆₀ (p < 0.05), VT-F0 (p < 0.05), and VT-P_max (p < 0.05) were observed but disappeared when these variables were expressed relative to body mass. Regarding the F–V profile determinants of sprinting performance, we observed significantly shorter sprint times in PHV compared to PHV−1 and in PHV+2 in comparison with the PHV+1 group. These between-group differences were associated with significant greater HZT-F0 kg⁻¹ (p < 0.05) and HZT-P_max kg⁻¹ (p < 0.001). However, significantly more negative value of HZT-Sfv kg⁻¹ was observed in PHV−1 compared to PHV−2 (p < 0.05), in PHV+1 in comparison with PHV (p < 0.05) and in PHV+3 when compared to the PHV+2 group (p < 0.05). Thus, these findings revealed an alternation of accelerated periods of development in force and velocity qualities, expressing sprinting performance, with maturation during the physical development process of young soccer players. Trainers and coaches should be aware of the distinct mechanical characteristics related to each maturity stage and design specific programs accordingly.

Load carriage training is universal during military training, regardless of sex or physical characteristics, and may contribute to the 1.3-2.2× higher incidence of patellofemoral pain (PFP) in female versus male recruits. This study aimed to assess sex differences in patellofemoral joint (PFJ) stress during load carriage, controlling for anthropometrics and quadriceps strength. Twenty males and 20 females walked (1.35 m/s) on an instrumented treadmill with 0-kg, 20.4-kg, and 34.0-kg of load carriage. An inverse-dynamics musculoskeletal model estimated peak, impulse, and cumulative PFJ stress. To assess quadriceps strength, peak isometric knee extensor torque normalized to body mass was measured via dynamometry. Analyses of covariance (ANCOVA) adjusting for body mass, height, and quadriceps strength assessed the effects of load (0-kg, 20.4-kg, and 34.0-kg) and biological sex (male, female) on PFJ stress and gait parameters. Females were shorter, had lower mass, and lower quadriceps strength (all p < 0.001; d = 1.50–1.54, indicating large effect sizes). Peak, impulse per step, and cumulative PFJ stress increased with load carriage, with greater increases in females compared to males (sex × load interactions p = 0.002–0.005; η_p² = 0.12–0.13, indicating moderate effect sizes) after controlling for body mass, height, and quadriceps strength. These data indicate that anthropometrics and quadriceps strength do not explain the substantially greater increases in per step and cumulative PFJ stress in females versus males with load carriage. Female recruits may benefit from targeted prevention efforts, such as slower progressions of load carriage training, either in amount carried or distance trained, to reduce their risk of PFP.

To assess whether certain players are more vulnerable to postmatch sleep disturbances by examining the relationship between match demands—collision frequency and locomotor load—and sleep in professional male rugby union players. A linear mixed-effects regression examined the relationship between match variables and sleep in 13 rugby players across three matches. Match variables included six physical demand variables derived from video analysis and GPS data (collision frequency, total distance, high-speed distance, sprint distance, acceleration load and fast acceleration count) and two contextual variables (location and kick-off time). Sleep variables collected via home-based polysomnography included total sleep time, sleep efficiency, sleep onset/offset, sleep onset latency, wake after sleep onset, number of awakenings and sleep stages (light, deep and rapid eye movement sleep [REM], evaluated both by proportion [%] and time [min]). Each match collision decreased total sleep time (β = −4 ± 1 min and p = 0.006) and REM sleep (time: β = −2 ± 0 min and p < 0.001; proportion: β = −0.6 ± 0.2% and p = 0.021). Conversely, every 500 m increase in locomotor load (total distance) increased REM sleep (time: β = +6 ± 2 min and p = 0.014; proportion: β = +2.7 ± 0.6% and p = 0.002). Every 100 m increase in high-speed distance was associated with decreased REM sleep time (β = −7 ± 3 min and p = 0.020). Match demands, including collision frequency and locomotor load, were associated with changes in postmatch sleep architecture in professional rugby players, particularly REM sleep. Furthermore, greater number of collisions was associated with reduced sleep quantity. Practitioners can leverage GPS and video analysis data to tailor additional sleep strategies aimed at improving postmatch sleep based on individual match demands.

Normative values for physical performance tests (PTESTs) offer insights into athletes' profiles on strengths and weaknesses to enhance performance and mitigate injury risks. However, such data for youth tennis players have not previously been compiled in a systematic review. We conducted a systematic review of 17 popular PTESTs covering speed, agility, strength, and power in healthy, competitive youth tennis players under the age of 8–18 years. A search for eligible studies indexed in the PubMed, Web of Science, Scopus, and Cochrane Library databases was conducted on the 26^th of March 2023. Forty-five studies (8008 players) were included and meta-analyzed. The analysis accounted for age, sex, and the use of dominant/nondominant sides. Many of the results were associated with a high level of statistical heterogeneity likely due to variations in test procedures. Data for players under the age of 8–10 years were generally lacking, and males were studied more than females. Higher age, male gender, and the use of the dominant side were generally associated with higher performance levels. In male players, the internal rotation of the dominant shoulder appeared to decrease with age, which may lead to injury. The review offers preliminary references for coaches, clinicians, and researchers to identify players' strengths and weaknesses, potentially aiding the enhancement of performance and the prevention of injuries.

Virtual reality (VR) offers opportunities to train and assess visuomotor skills and sports performance in controlled, reproducible contexts, supporting innovation in research and training. However, VR imposes unique sensory demands that may disrupt movement coordination, task performance, and potential skill learning. This study used putting performance assessment and eye-tracking to examine visuomotor coordination and performance in VR versus the real world, and whether effects varied by task expertise and athlete skill. Novice undergraduates (n = 44), national/international athletes in sports other than golf (n = 14), and expert golfers (n = 5) completed 30 putts in both settings while eye-gaze and putting outcomes were measured. Novices were divided into low performing (LPN) and high performing (HPN) based on real-world performance, while athletes and experts were not. More putts were holed in the real-world than VR across expertise groups, while experts holed many more putts in the real-world than athletes, HPN, and LPN, while athletes and HPN holed more putts than LPN. There were no differences between groups in VR holed putts. Putting radial error (RE) was much lower for experts, and moderately lower for athletes and HPN than LPN in the real-world. Experts had moderately lower RE than HPN in VR. Quiet Eye (QE), the final fixation prior to movement execution, predicted reduced RE for experts in the real-world but not in VR. Visuomotor co-ordination in VR may be disrupted. VR training environments may need adjustment to address visuomotor differences and should be designed to deliver feedback consistent with real-world performance expectations.

The effect of exercise-induced muscle damage (EIMD) on three-dimensional side cut biomechanics and task achievement were assessed in 16 team sport athletes (eight males and eight females) who completed 45° side cuts before and 48 h after multidirectional running. Angular displacement and joint moments of the hip and knee, and GRF impulse (IGRF) during five successful trials of a 45° side cut, were collected using a 3D motion capture system and force platform at both timepoints. At 48 h, participants had more knee internal rotation (p = 0.009), knee abduction ROM (p = 0.002), lower peak knee extensor moment (p = 0.001) and a higher hip-knee extensor ratio moment (p = 0.020). Large increases in IGRF at 48 h in females (d; ± 95% CI: 1.4; ± 1.4, p = 0.037) suggest a less effective deceleration capacity. Whilst EIMD had no effect on side cut task achievement and sagittal kinematics, EIMD caused participants to shift the extensor demands away from the knee and towards the hip to decelerate the body. Practitioners should be mindful of potential increases in frontal and transverse motions at the knee for athletes with EIMD, which might have implications for strategies to reduce injury risk.

Based on the goal progress theory, we examined whether cueing an unresolved goal triggers state rumination in athletes and consequently leads to performance deterioration. However, experimental approaches are usually conducted in the laboratory and only rarely in the field. Therefore, the aim of this proof-of-concept study was to verify whether the findings obtained in previous experimental studies could be transferred and confirmed in the field. For this purpose, the study was applied during regular training sessions. Fifty soccer players (f = 17, m = 33, age range: 14–18 years; M_age = 16.38) were divided into three different conditions—one experimental condition in which a goal-related rumination was induced and two control conditions in which a comparable goal-related induction or a neutral task was performed. Before and after the inductions during athletic practice, soccer players performed a sport-specific test to examine potential changes in athletes' performance as a function of condition and answered questions related to their state rumination. Different mixed ANOVAs were performed to examine (1) whether we could significantly elicit rumination in soccer players and (2) whether the application of the experimental procedure had an impact on performance in the subsequent sport-specific test. Two main findings were identified: First, the experimental procedure generally transfers well to the field. Second, however, the expected effects of state rumination on performance in the sport-specific test were not obtained. Reasons for the lack of clear effects and approaches for future research are discussed.