International journal of sports medicine最新文献

The purpose of the current study was to identify the influence of individual characteristics on differences in body fat percentage between air displacement plethysmography and dual-energy X-ray absorptiometry (change in body fat percentage) in 360 collegiate student-athletes. Body fat percentage was obtained from air displacement plethysmography and dual-energy X-ray absorptiometry. A 2 (sex)×3 (Brozek body fat percentage, Siri body fat percentage, and dual-energy x-ray absorptiometry body fat percentage) analysis of variance was used to evaluate the difference between the body fat percentages obtained from air displacement plethysmography and dual-energy x-ray absorptiometry in men and women. The agreement between air displacement plethysmography and dual-energy X-ray absorptiometry was evaluated via Bland-Altman plot and linear regression. Multiple linear regression was used to identify the influence of sex, race, height, and body mass on the change in body fat percentages. Dual-energy X-ray absorptiometry yielded greater body fat percentages in both men (4.8±2.8; p < 0.001) and women (2.2±2.9; p < 0.001) compared to air displacement plethysmography measurements. Proportional and systematic biases were observed between air displacement plethysmography and dual-energy X-ray absorptiometry. Race, height, and mass were significant predictors of the body fat percentage difference between air displacement plethysmography and dual-energy X-ray absorptiometry (R ²=0.445, p<0.001, and standard error of the estimate=2.527). The present study suggests that air displacement plethysmography underestimates body fat percentages when compared to dual-energy X-ray absorptiometry and this underestimation may not be the same for every athlete due to their individual characteristics.

The present study aimed to investigate the development of physical performance attributes across one competition year in male youth soccer players from different playing levels, while controlling for baseline performance, chronological age, and biological maturity. A total of 175 male Scottish youth soccer players from three distinct playing levels: grassroots (GR); professional youth (PY); performance school (PS) were recruited. Physical testing (linear sprint, change of direction, squat jump, and Yo-Yo Intermittent Recovery Test Level 1) was conducted for all players to establish baseline fitness and then repeated under matched conditions at the end of the same competition year. A Bayesian approach was used to estimate the size of any change in each physical test over the season, estimate the uncertainty around these changes, and estimate the probability of direction of these changes. In all cases, the players improved fitness testing metrics. The GR group made the greatest changes in physical performances but did not match absolute performance of the PY and PS groups. Our results provide meaningful benchmark data for evaluating and interpreting isolated physical fitness metrics between distinct youth playing levels and may augment the ongoing critique of the discriminative ability of isolated physical fitness tests in youth soccer.

Periodontitis is a chronic inflammatory condition that involves bone resorption and leads to tooth loss. This study aimed to evaluate the biological plausibility of exercise's potential impact on periodontal repair in rats. Forty-eight male Wistar rats received cotton ligatures around the lower first molars, bilaterally. After 7 days, all animals were allocated to the following groups: Control (ligature removal), Early Treatment (ligature removal+Exercise) and Late Treatment (Exercise alone for 28 days, then ligature removal) (n=16/group). All groups were evaluated at 28 and 56 days. Swimming exercise was performed 5 days/week. Mandibles, blood and gingiva were collected for radiographic, histological and inflammatory analysis using multiplex. At 56 days, both exercise groups showed significantly lower bone loss compared to the Control group. Histological analysis revealed that Early Treatment promoted increased percentages of fibroblasts and blood vessels. Late Treatment provided statistically higher serum Vascular Endothelial Growth Factor levels than Early Treatment or Control groups. In gingiva, Epidermal Growth Factor was significantly higher in the exercise groups compared to Control. In conclusion, late or early treatment including exercise improved bone repair in rats, possibly through growth factor modulation.

This systematic review/meta-analysis aimed to evaluate the effects of resistance exercise on ambulatory blood pressure (ABP). PubMed, Web of Science, Scielo, Embase, and Scopus databases were searched for crossover/controlled trials of resistance exercise in adults compared to a control group/condition from inception until May 2025. Mean differences with 95% confidence intervals were calculated (p<0.05 significant). Risk of bias was assessed by the Cochrane risk-of-bias tool for randomized trials. Twenty-six studies were included: 18 acute (immediate, short-term, including 351 participants) and 8 chronic (long-term, including 356 participants), with mostly unclear/high risk of bias. Acutely resistance exercises led to lower 24-hour diastolic blood pressure (BP) in subjects with chronic diseases (-1.15 mmHg;-2.08,-0.22; p=0.020), and lower daytime diastolic BP in healthy participants (-0.77 mmHg,-1.51,-0.03; p=0.040). Chronically resistance training lowered 24-hour systolic (-3.99 mmHg;-7.59,-0.39; p=0.030) and diastolic BP (-1.52 mmHg;-2.67,-0.37; p=0.009) and daytime systolic/diastolic BP in subjects with chronic diseases (Systolic:-5.53 mmHg;-8.83,-2.23; p=0.001; Diastolic:-1.86 mmHg;-3.11,-0.61; p=0.003). In conclusion, resistance exercise promotes modest reductions in ABP, especially among individuals with chronic diseases. The most consistent effects were observed for 24-hour and daytime systolic and diastolic BP. Acute reductions were smaller and limited to daytime diastolic BP.

The After-Career Consultation (ACC) was developed to empower the physical, mental and social health of retired professional footballers and effectively address their specific health challenges. The objective of this study was to describe the clinical outcomes (e.g., prevalence of health conditions) and recommendations to retired professional footballers who undertook the ACC. A quasi-experimental study was conducted. Forty-seven retired male professional footballers underwent ACCs. Ten participants had a diagnosis of osteoarthritis (21.3%), 4 (8.5%) met the criteria for a diagnosis of generalised anxiety disorder, 7 (14.9%) met the criteria for a diagnosis of depression and 7 (14.9%) met the criteria for Stage 1 hypertension. Health-related quality of life scores among retired footballers undergoing the ACC were above average compared to the general population. Clinical recommendations were made to participants in relation to their musculoskeletal (n=12, 25.5%), cardiovascular (n=12, 25.5%), mental (n=10, 21.3%) and lifestyle (n=20, 42.6%) health. Eleven participants (23.4%) were referred for further investigations, and secondary referral to other specialists was arranged for 4 (8.5%). Participants reported high satisfaction with the ACC. The ACC could complement existing player welfare strategies to provide a well-rounded approach to managing the long-term health of professional footballers throughout the lifespan.

This study investigated whether, 24 hours after the exercise-induced muscle damage protocol (EIMDP), melatonin administration performed 30 minutes prior to the protocol exhibited responses about inflammatory and redox status. Control (CG), exercised (EG), and exercised+melatonin (EMG) groups were submitted to the incremental test through swimming exercise to determine the intensity of the maximal aerobic capacity (iMAC). Melatonin (10 mg kg^-1) was administered, and after 30 min, the EIMDP was induced through swimming exercise (10 sets of 1 min with 30-s interval at 120% of iMAC, followed by 20 minutes continuous exercise at 100% of iMAC). The animals were euthanized 24 hours after the EIMDP. No effect on superoxide dismutase but lower activities (p<0.05) of glutathione S-transferase for EMG in relation to EG and of catalase for EMG in relation to CG were observed. EMG showed lower (p<0.05) carbonylated protein and lipid peroxidation in relation to EG and CG, respectively. Hematoxylin-eosin (HE) demonstrated higher connective tissue for EG in relation to EMG. Integrated Biomarker Responses version 2 attested the melatonin capacity in reducing antioxidant enzyme activity and muscle oxidative damage. This study demonstrated the protective role of melatonin in reducing muscle oxidative stress caused after 24 hours of the EIMDP.

The aim of this study was to evaluate the predictive capacity of functional electromechanical dynamometry for sprint canoe performance. Twenty-one world-class sprint canoeists underwent two functional electromechanical dynamometry assessments (isometric and incremental load) in the sprint canoe-specific kneeling position. Race performance was assessed via official C1 500-m race times. Significant negative correlations were observed between 500-m race times and both the mean force (r=-0.72; p=0.001) and the peak force (r=-0.71; p=0.001) measured through the isometric dynamometric test. In the incremental test, a strong negative correlation was found between the race time and the number of strokes (Nreps; r=-0.85; p=0.001), as well as the absolute peak force (r=-0.80; p=0.001). These relationships remained significant when force values were adjusted for body mass. The strongest predictive model (R² _a=0.73) included the number of strokes from the incremental load test (C1 500-m race time=170.30-3.29 Nreps). These findings support the use of functional electromechanical dynamometry as a valid and sport-specific tool for assessing neuromuscular performance in elite sprint canoeists.

The effects of estradiol and progesterone fluctuations during the menstrual cycle (MC) on strength and fatigue remain unclear. This study investigated their impact on peak torque and fatigue in isokinetic tests. Eleven strength-trained women performed five knee extensions and flexions to assess maximum peak torque, rating of perceived exertion (RPE), and rating of perceived pain (RPP). A separate protocol of 60 repetitions was used to evaluate peak torque, total work, percentage of work fatigue, RPE, RPP, and blood lactate concentration before and after exercise. MC phases were determined using a combination of calendar tracking, urinary ovulation tests, and serum hormone analysis. A one-way repeated-measures analysis of variance, followed by Bonferroni's post hoc tests and effect size calculations (partial eta-square), analyzed differences across six MC phases. No significant differences were observed in peak torque, RPE, or RPP during knee extension and flexion (p>0.05). Similarly, fatigue parameters assessed during the 60-repetition test showed no significant variation across MC phases (p>0.05). However, blood lactate concentrations were significantly higher postexercise than preexercise (p<0.05). These findings suggest that strength performance and muscle fatigue are not influenced by hormonal fluctuations across the MC in strength-trained women.

Research on chronic aerobic exercise (AE) and arterial stiffness has yielded mixed results, largely due to differences in participant characteristics and training protocols. This meta-analysis included 26 trials (40 interventions; n=756; average age 42±15 y) to assess AE's effect on arterial stiffness, measured by pulse wave velocity (PWV) and to explore moderating factors. AE programs averaged 40±19 minutes/session, 3±1 d/wk, over 11±8 weeks, with intensities between 3 and 8 METs. Random-effects analysis showed AE significantly reduced central (- 1.02 m/s), mixed (- 0.34 m/s), and peripheral (- 0.72 m/s) PWV, with an overall mean reduction of-0.93 m/s and no differences between arterial beds. However, only a subset of studies showed significant reductions: 9/25 for central, 3/6 for mixed, and 4/8 for peripheral PWV. Studies with higher methodological quality yielded larger effect sizes. Reductions in PWV were consistent across participants with normal or high blood pressure, differing baseline PWV, and both younger and older adults, regardless of blood pressure changes. The impact of training components was inconsistent, suggesting AE benefits across a range of intensities and volumes. Overall, AE appears to reduce arterial stiffness across diverse populations and exercise protocols, supporting its role in improving vascular health.

The aims of this research were to identify the relationships between the total genotype score and the total competition time as well as the total and relative distances covered during competition at different speed thresholds and to examine the probability of being a starter or a non-starter based on the total genotype score. A prospective pilot study was conducted with 34 professional male football players competing in the Spanish second division across three consecutive seasons. DNA samples were genotyped for six muscle performance-related polymorphisms, and the total genotype score values were calculated. The total competition time and competition distances at different speed thresholds were evaluated. A total genotype score threshold of 75.0 a.u. discriminated starters with an area under the curve of 0.689. Players with higher total genotype scores (total genotype scores: >75.0) accumulated more matches played (p=0.002), more matches played as starters (p=0.009), greater playing time (p=0.009), and higher total distances covered (p=0.009). Players above this threshold were five times more likely to be starters (odds ratio=5.00, 95% confidence interval: 1.31-19.07, and p=0.030). The total genotype score was related to the number of matches played (β=1.088 and p=0.006), matches as starters (β=1.087 and p=0.004), playing time (β=28.1 and p=0.018), and distances covered during the seasons (β=3116 and p=0.01). Genetic profiling was associated with starter status. Integrating genetic and global positioning system data provided a novel approach for player development and talent identification in elite sports.