International journal of sports physiology and performance最新文献

Purpose: The purpose of this research was to report isometric hip adduction and abduction strength reference values of men's and women's Gaelic football and rugby union players and compare values between sexes and between sports.

Methods: This cross-sectional cohort study consisted of 331 club-level athletes. Maximum isometric hip adduction squeeze and abduction press strength values were measured with a ForceFrame across several testing positions.

Results: Hip adduction squeeze and abduction press strength reference values for men's and women's Gaelic and rugby union footballers were provided with mean and 1 SD. A 2-way analysis of variance demonstrated significant sport × sex interaction main effects for hip adduction squeeze (η2 = .159-.228), abduction press (η2 = .099-.144), and adduction:abduction ratio (η2 = .120). Men demonstrated significantly greater relative (Newtons per kilogram) maximum isometric hip adduction squeeze (15.5%-26.4%, 0.48-1.00 N/kg) and hip abduction press (9.6%-19.6%, 0.20-0.67 N/kg) strength across all testing positions when compared with women of the same sport. Male Gaelic football players demonstrated significantly greater hip adduction (8.7%-14.0%, 0.30-0.52 N/kg) and abduction (6.1%-8.6%, 0.16-0.31 N/kg) strength (Newtons per kilogram) than their rugby counterparts, while no significant between-sports differences in strength were observed between female athletes.

Conclusion: Reference values are provided with mean and 1 SD. Sport and sex interaction had significant main effects for hip adduction, abduction, and adduction:abduction ratio, with medium to large effect sizes. Male athletes demonstrate significantly greater hip strength than female athletes of the same sport, and male Gaelic players demonstrate greater hip strength than male rugby players.

Predictions of performances should be evaluated to confirm their accuracy. Work by this group has resulted in 3 sets of predictions being generated for swimming events at the Paris 2024 Olympic Games, using the same statistical approach for each set.

Purpose: To examine the accuracy of swimming predictions for the Paris 2024 Olympic Games and generate updated predictions for both the Singapore 2025 World Aquatics Championships and Los Angeles 2028 Olympic Games.

Methods: A linear regression and forecasting function was used to generate predictions for the Paris 2024 Olympic Games across 3 performance categories (rank 1st-3rd, 4th-8th, and 9th-16th). Mean absolute error was used to assess the accuracy of the predicted versus actual Paris 2024 Olympic Games times for all events across the 3 performance categories. New predictions for the 2028 Olympic cycle were subsequently generated using results from the World Championships and Olympic Games between 2011 and 2024.

Results: Across all events, a mean absolute error value of 0.84% was observed between the Paris 2024 Olympic Games predicted and actual times. Predicted times were highly correlated with actual times (r2 = .99). Across the 3 sets of predictions (created in 2022, 2023, and 2024), the 2023 set of predictions had the lowest overall mean absolute error value (0.55%).

Conclusions: The methods used to create predictions for swimming performances at the Paris 2024 Olympic Games were deemed accurate. These methods enable national swimming federations to create a series of predictions for a given major championship, inform athlete identification and development pathways, and allocate appropriate resources, including sport-science provision.

Background: Travel can disrupt sleep and reduce perceived recovery in athletes. While the impact of travel on physical performance has been studied, its effect on cognitive performance remains unexplored.

Purpose: This study investigated the consequences of overnight long-haul travel on physical (part I) and cognitive performance (part II) in professional rugby players traveling overseas for competition.

Methods: In part I (n = 24), vertical-jump performance was assessed across 5 mornings surrounding travel (HOME, TRAVEL, and AWAY 1, 2, and 3). In part II (n = 24), mental fatigue and psychomotor vigilance (defined as the ability to respond to stimuli effectively) were assessed across 3 days (HOME, TRAVEL, and AWAY 1). Sleep was monitored on all nights preceding performance assessment using activity monitoring.

Results: Compared with HOME, TRAVEL reduced sleep quantity (part I. -219 [112] min; part II, -334 [233] min; both P < .001) and elevated in-flight mental fatigue (part II, +12 [18]; P < .05). Psychomotor vigilance was impaired during TRAVEL (+8% [6%] in valid response latencies ≤500 milliseconds; P < .001), and reactive jump strength was reduced at AWAY 1 (-7% [10%] in drop jump; P < .001). While psychomotor vigilance was restored by AWAY 1 (after hotel sleep), reactive jump strength remained diminished until AWAY 3 (-12% [9%] in drop jump compared with HOME; P < .001) after travel.

Conclusion: For teams traveling on long-haul journeys overnight for competition, it is recommended to arrive more than 3 days before matches to enable sufficient physical and cognitive recovery at the new destination to optimize performance away from home.

Purpose: To examine the association between reactive strength index (RSI) and metabolic cost of running (MCr) in master athletes. We hypothesized that individuals with a higher RSI would exhibit a lower MCr, that both variables would be associated, and that age would moderate this relationship.

Methods: Forty-five male master athletes participated to this study. A median split was performed to constitute 2 age groups (group 1, 47.7 [1.7] y old; group 2, 56.3 [4.6] y old). Participants underwent a single 45-minute session during which RSI was assessed with drop jumps, and MCr, during a continuous exercise of submaximal intensity performed on a treadmill.

Results: A small negative association was found between net MCr and RSI in the overall sample (RSI mean r = -.38, P < .05; RSI max r = -.38, P < .05). Group 1 exhibited a lower net MCr (P < .01, d = -0.84) and higher RSI (P < .01, d > 0.82) than group 2. However, the association between the 2 measures was verified specifically in group 2 (RSI from a 20-cm drop jump, r = -.53, P < .01; RSI mean, r = -.50, P < .05; RSI maximum, r = -.57, P < .01).

Conclusions: RSI is associated with net MCR in master athletes, particularly in older participants. Additional intervention studies are now required to further explore this association.

Purpose: (1) To analyze the effects of postactivation performance enhancement (PAPE) induced by upper-limb flywheel resistance training on serve velocity and accuracy in tennis players, (2) to compare the effects of 2 different protocols (low load [LL] vs high load [HL]), and (3) to examine whether PAPE effects are influenced by tennis players' neuromuscular performance.

Methods: Fifteen young competitive tennis players completed 1 familiarization and 3 testing sessions in a randomized order. In the control session, participants performed a warm-up protocol followed by serve-velocity and -accuracy tests. The experimental sessions included 3 sets of 6 repetitions of LL (0.02 kg·m2) or HL (0.08 kg·m2) flywheel shoulder internal rotation prior to the serve-velocity and -accuracy tests. Serve velocity and accuracy were measured at 30 seconds and 3 and 6 minutes after each protocol.

Results: There were moderately significant serve-velocity differences between baseline and LL protocols at 3 (P = .009; 5.4% [5.8%]; effect size = 0.927) and 6 minutes in both LL (P = .025; 5.7% [7.2%]; effect size = 0.793) and HL (P = .026; 5.4% [6.8%]; effect size = 0.787) protocols. Serve accuracy remained stable in both protocols and recovery times. No associations were found between mechanical outcomes and percentage changes.

Conclusions: Low volume and multiple sets of shoulder internal-rotation flywheel resistance training induced serve-velocity PAPE in competitive tennis players without serve-accuracy impairment in time windows from 3 to 6 minutes. Better neuromuscular performance did not seem to favor PAPE effects.

Purpose: Previous research has primarily focused on bounce drop jump (BDJ) rather than countermovement drop jump (CDJ) in studying optimal drop heights for drop jump. This study explored the biomechanic parameters of both BDJ and CDJ and their relationship with performance across varying drop heights based on the percentage of squat-jump height (SJH).

Methods: Twenty-four college basketball athletes were recruited and divided into low- and high-strength groups. Participants performed BDJ and CDJ at 50%, 75%, 100%, 125%, 150%, and 175% of SJH. The point or zone with the largest reactive strength index (RSI) corresponds to the optimal drop height for a drop jump.

Results: Optimal drop heights were determined to be 84.7% of SJH for BDJ low strength and 84.1% of SJH for BDJ high strength, with no significant difference between groups (P = .213). For CDJ, relative optimal drop heights were 104.6% of SJH for CDJ low strength and 106.1% of SJH for CDJ high strength, also with no significant difference (P = .717). Mechanical power with RSI exhibited a coefficient close to 1 (r = .98-.99), while average propulsive force demonstrated a very strong positive correlation with RSI (r = .72-.77).

Conclusions: It is recommended that basketball athletes incorporate particular percentages of SJH into drop jump, with 75% to 100% of SJH for BDJ and 100% to 125% of SJH for CDJ, as these heights are associated with achieving an optimal RSI and mechanical power. Tailoring the inclusion of BDJ or CDJ in training should account for the specific demands of on-court positions and task objectives for basketball players.

Purpose: Confirmation bias, a cognitive phenomenon deeply ingrained in human thinking, shapes our perception of reality. It leads individuals to favor information that aligns with their preexisting beliefs while dismissing or undervaluing the contrary evidence. In sport science, where precision and evidence-based practices are critical aspects to optimize performance, confirmation bias can decisively impact decision-making processes. In this context, practitioners rely on both objective and subjective data to be interpreted to enhance athletic performance. However, confirmation bias introduces a subtle yet powerful distortion, which is difficult to control and quantify. We usually believe that our observations can justify expectations or predictions about future observations, as well as broader generalizations beyond what we have directly observed-inductive inferences. Researchers and practitioners may therefore unknowingly seek out evidence that confirms their beliefs, inadvertently overlooking alternative viewpoints and interpretations.

Conclusions: This paper explores the concept of confirmation bias in sport science, providing practical examples in the contexts of testing, training, and monitoring. By understanding how confirmation bias operates (ie, heuristic of decision making), we may develop strategies to mitigate its effects and promote more accurate and effective decision making in sport science (eg, performance).

Purpose: Although women's futsal has experienced great growth recently, few studies have analyzed the physical profiles of female futsal players. The objectives of this study were to determine the physical and anthropometric characteristics in elite women's futsal using laboratory and field tests and to analyze the differences between the different playing positions.

Methods: Forty-one female futsal players from the second division of the Spanish league (age 22.69 [4.76] y; body height 161.28 [6.03] cm; body mass 62.20 [10.34] kg) were evaluated for body composition with dual-energy X-ray absortiometry anthropometrically, lower-body power using a force platform (countermovement jump, squat jump, and drop jump), linear speed (5, 10, 15, and 25 m), changes of direction (505 modified, V-Cut, and L-Run), and repeated-sprint ability measured through photoelectric cells.

Results: The results reveal that there are no significant differences between the physical profiles of players depending on playing position. Despite this, wingers seem to have the best physical profiles, and goalkeepers have the highest body mass index (26.9 [4.48] vs 23.3 [2.82]; P = .069) and fat percentage (31.9 [7.81] vs 29.96 [6.08]; P = .101), but they present very similar values to the other positions in all other tests performed, except for repeated-sprint ability (4.64 [0.45]; P = .009).

Conclusion: Relevant descriptive data were presented to provide useful information for coaches to optimize their training programs, reporting that playing position does not identify different physical profiles in elite female futsal players.

Purpose: The present study analyzed the effects of a maximal-power-endurance (MPE) versus a repeated-power-ability (RPA) training program on different strength, power, and repeated-power measurements in a short- and long-term training period and the relationships between changes in all variables.

Methods: Twenty-two young highly trained male basketball players were randomly allocated to 1 of the 2 groups (MPE, n = 11; RPA, n = 11) and evaluated by 1-repetition maximum and incremental load, RPA, and MPE tests in the bench-press exercise before and after a period of 4 and 8 weeks. The MPE group performed 2 to 4 sets of a postdetermined number of repetitions (ie, set stopped when maximum power output decreased >10%) using the load that maximized power output. The RPA group carried out 1 to 3 blocks of 5 sets of 5 repetitions with a load that maximized power output.

Results: Both groups significantly (P < .001; effect size = 0.58; 1.56) improved 1-repetition maximum, maximum power output, and 20%, 40%, 60%, and 80% of 1-repetition maximum from pretest to posttest in the incremental load test. Significant improvements (P < .001) were found for the RPA and MPE groups in the best, mean, and last set in the RPA test at all times. Furthermore, a significant (P < .001) time × group interaction was found in the MPE test, showing significant improvements in both groups at posttest. In addition, at posttest, intraset power fluctuation in the mean was significantly (P < .05; effect size = 0.45) better in MPE group compared with RPA group.

Conclusion: In conclusion, both training programs represent appropriate methods to improve neuromuscular measurements, although MPE training seems to be a more volume-efficient strategy (∼50% fewer repetitions) to enhance several fatigue-resistance indexes (intraset power fluctuation in the mean).

Purpose: Pacing is crucial in endurance sports such as running, and its importance is also prominent in trail running due to the unique challenges, including high elevation gains and varied terrain. This study aimed to explore the pacing strategies of elite athletes during the 2023 World Mountain and Trail Running Championships for the Trail Short distance.

Methods: The participants included 12 elite trail runners who provided their race data from sport watches for analysis.

Results: The findings indicate a significant decrease in grade-adjusted pace (vi) as the race progressed, with an average change of -18.7% from the start to the last downhill segment. A linear correlation of -.55 (P = .031) was observed between the winning time and the evolution of vi, suggesting that more consistent pacing led to better performance. The Student t test (t = 2.628, numerator degrees of freedom = 10, P = .013) confirmed that even pacing is significantly correlated with superior race results at a confidence level above 95%.

Conclusions: A more even pacing strategy is associated with success during elite trail-running races.