Journal of Sports Medicine and Physical Fitness最新文献

Introduction: Down syndrome (DS), caused by an extra chromosome 21, leads to physical and cognitive challenges. Physical activity is underutilized as a therapeutic approach. This study reviews the effectiveness of physical exercise in improving body composition and health outcomes in individuals with DS.

Evidence acquisition: Following PRISMA guidelines, this review was registered on PROSPERO (CRD42024561407). A systematic search across six databases identified randomized controlled trials (RCTs) involving physical activity interventions in DS populations compared to controls. Data were analyzed using a random-effects model, with heterogeneity assessed through REML, Q-test, and I². Risk of bias was evaluated using RoB 2.

Evidence synthesis: From 245 records, 13 RCTs (447 participants from eight countries) met inclusion criteria. Interventions lasted 6 to 43 weeks, with 1 to 5 sessions per week. Body mass decreased significantly (SMD: -0.2099, 95% CI: -0.3539 to -0.0658). BMI and body fat also reduced significantly (SMD: -0.2369 and -0.4255, respectively). Waist circumference showed no significant changes, but favorable trends were noted. Muscle strength improvements in chest and leg press were positive but not statistically significant.

Conclusions: Physical exercise significantly improves body composition in individuals with DS, notably reducing body mass, BMI, and body fat. These findings highlight the value of structured physical activity as part of DS management to improve health and quality of life.

Background: Blood flow restriction (BFR) implemented during aerobic exercise has been shown to alter cardiopulmonary responses under intensity-matched conditions, but its effects relative to maximal running speed and the gas exchange threshold (GET) remain unclear. The purpose of this investigation was to examine cardiopulmonary (oxygen consumption [V̇O2] and carbon dioxide production [V̇CO2]) responses during submaximal running with BFR relative to maximal running without BFR and the GET.

Methods: Fifteen aerobically trained females completed a custom ramp protocol to determine peak running speed and GET. Participants randomly completed four, three-minute running bouts at 70%BFR, 80%BFR, and 90%BFR of their top speed with BFR and 100%NOBFR of their top speed without BFR. Separate Bayesian repeated-measure models were performed to examine differences in V̇O2 and V̇CO2 during the final minute of the bouts.

Results: V̇O2 largely increased across bouts but was similar between the 80%BFR and 90%BFR (Meandiff=-2.26±-0.44 mL·kg^-1·min^-1) bouts as well as the 90%BFR and 100%NOBFR (Meandiff=-2.54±0.03 mL·kg^-1·min^-1) bouts. V̇CO2 also increased across bouts and was similar between the 90%BFR and 100%NOBFR (Meandiff=-0.25±-0.02 L·min^-1) bouts. Relative to GET, V̇O2 and V̇CO2 was greater during each bout (GET < 70%BFR, 80%BFR, 90%BFR, and 100%NOBFR).

Conclusions: Pulmonary gas exchange during submaximal running with BFR was comparable to maximal running without BFR (i.e., 90%BFR and 100%NOBFR) and greater than speed-matched running (i.e., relative to GET). Thus, BFR may serve as a training adjunct to lower the intensity (i.e., ≤10%) relative to the GET.

Background: This study evaluated the effects of external focus distance for novice soccer players to determine motor skills and enhancing shooting accuracy in soccer. Soccer demands a unique combination of physicality and technical finesse, with precision, accuracy, and ball-handling skills distinguishing great players. This study aims to investigate the impact of different external focus cues on the shooting accuracy of novice male soccer players during a crossbar challenge. It aims to provide insights for coaches and players to optimize training techniques for skill development.

Methods: The study involved 45 male participants aged 18-25 who were assigned to the distal external focus, proximal external focus, and control group. Participants performed a practice trial followed by five experimental trials with specific focus instructions. Shooting accuracy was measured using the Loughborough Soccer Shooting Test. Statistical analysis was done using SPSS version 20, which included a mixed paired t-test and one-way ANOVA to compare the group performances.

Results: Participants with a distal external focus (M=2.4080) group consistently achieved the highest scores, followed by the proximal external focus group (M=1.5573), with the control group (M=1.3467) having the lowest scores.

Conclusions: The study shows that, in comparison to a proximal external focus and a control group, a distal external focus significantly increases soccer shooting accuracy. These findings provide valuable insights for optimizing motor skills and enhancing shooting accuracy in soccer.

Background: This study aimed to determine the effects of changes in muscle mass and quality on muscle function and physical performance following an 8-week resistance training (RT) intervention.

Methods: Thirty-three healthy young women (23.1±2.2 years) underwent high- or low-velocity concentric knee extension RT at 60% one-repetition maximum strength (1RM) load for 10 repetitions × 4 sets, 3 times a week for 8 weeks. Before and after the RT intervention, quadriceps femoris muscle thickness (MT) (muscle mass index) and echo intensity (EI) (muscle quality index) were measured using B-mode ultrasound. Muscle function, including maximum isokinetic muscle strength, 1RM, rate of velocity development (RVD), and peak power, was assessed. Physical performance was evaluated using the countermovement jump (CMJ). Percentage changes (%change) in all parameters before and after the intervention were calculated for subsequent analyses. Multiple regression analysis was used to examined the contributions of changes in EI and MT to various muscle functions and physical performance, with the intervention group included as the covariate.

Results: MT %change was associated with 1RM %change (std.β=0.51, P=0.003), whereas EI %change was correlated with RVD %change (std.β=-0.39, P=0.025), peak power %change (std.β=--0.39, P=0.025), and CMJ %change (std.β=-0.44, P=0.011).

Conclusions: RT-induced increases in muscle mass contributed to improvements in 1RM, whereas enhancements in muscle quality were associated with gains in peak power, RVD, and CMJ. These results suggest training programs aimed at improving dynamic explosive performance in young adults should not only target muscle hypertrophy but also incorporate strategies to enhance muscle quality.

Plantar fasciopathy is a prevalent cause of heel pain, often mischaracterized as an inflammatory condition. It primarily affects individuals aged 40 to 60, with risk factors including foot biomechanics, obesity, and prolonged standing. Diagnosis relies on clinical assessment, incorporating validated tests such as the Windlass and Foot Posture Index tests, alongside imaging when necessary. Treatment follows a stepwise approach based on foot morphology, starting with conservative measures such as activity modification, targeted stretching of the plantar fascia and calf muscles, footwear optimization, and orthotic support. If symptoms persist beyond 8-12 weeks, shockwave therapy and, in refractory cases, corticosteroid or platelet-rich plasma injections may be considered. Surgery remains a last resort. A personalized treatment strategy based on biomechanical evaluation and patient-specific factors is crucial for successful outcomes. This guide provides an evidence-based framework for clinicians to accurately diagnose and effectively manage plantar fasciopathy.

Background: Match running performance is crucial for evaluating physical demands in elite soccer, with potential differences across age categories. Understanding these differences is essential for optimizing the physical preparation and career progression of young players. This study aimed to compare match running performance among senior, under-20 (U20), and under-17 (U17) elite soccer teams.

Methods: Data were collected from FIFA World Cup 2022, U20 World Cup, and U17 World Cup 2023 from the FIFA website. Running performance was assessed at both the team level and the individual level. Key performance variables included total distance covered (TD), distance across five running zones, sprints (SPR), high-speed runs (HSR), and maximum sprinting speed (MSS). Linear mixed model was used to compare performance across the three age groups.

Results: No significant differences between senior and U20 teams in most variables (all P>0.05) were observed, except for walking distance, which favored the senior teams in both team and individual performance (P<0.05). U20 teams covered greater distances in jogging and moderate speed running (MSR) (team performance), and jogging distance (individual performance) compared to senior teams (P<0.05). Senior and U20 teams generally outperformed U17 teams in most variables (P<0.05), except for walking distance, where U17 teams performed higher than U20 teams (P<0.001), with no significant differences between U17 and senior teams (P>0.05) for individual performance. Additionally, U17 teams showed similar performance to senior teams in jogging distance (team performance) (P>0.05).

Conclusions: Senior and U20 teams consistently outperformed U17 teams in most variables, except for walking distance. These findings provide valuable insights into the physical demands of match play across age groups.

Background: This study examines sports-related concussions (SRC) experiences, beliefs, and behaviors among male and female teenage grassroots soccer players in the UK, focusing on how these are shaped by interpersonal and mediated relations with coaches, parents, and peers.

Methods: A cross-sectional cohort study informed by interpretivist epistemology and qualitative research design. Data collection involved focus groups, using a topic guide covering SRC knowledge, attitudes, behaviors, and reporting intentions. Focus group sessions were conducted between July 2023 and April 2024. Participants were enrolled through convenience and snowball sampling at a single grassroots soccer club in the UK. Three cohorts of male participants (N.=15) and one cohort of female participants (N.=5) participated in three focus groups each. The 12 focus groups were held at the grassroots soccer academy with the club welfare officer present. Sessions were digitally recorded, transcribed, and analyZed using a framework analysis model.

Results: Participants identified and recognized many symptoms associated with SRC, though knowledge was mainly acquired through informal channels (e.g., the media). However, this understanding did not lead to safety-related behavior changes, with significant non-compliance observed among players, parents, and coaches.

Conclusions: Effective SRC management requires tailored education programs to overcome barriers and promote safety within grassroots youth soccer. Addressing gender norms and enhancing education can foster a culture of support and accountability, safeguarding the well-being of young athletes. There is a need for better awareness and more precautionary behaviors among all stakeholders in grassroots soccer.

Background: Soccer is the most practiced sport globally, and adequate dietary intake can significantly impact athletic performance. This study aimed to assess the nutritional knowledge of semi-professional and professional Italian soccer players and evaluate whether their dietary intake aligns with international recommendation for elite soccer players.

Methods: Male players from two Italian football league teams (one in Category C, one in Category D) participated during the regular season. Demographic and anthropometric data were collected during the initial visit. Nutrition knowledge was evaluated using a simplified version of the "Nutrition for Sport Knowledge Questionnaire" (NSKQ). Participants completed a 4-day food diary and dietary data were compared against dietary references for elite athletes and soccer players.

Results: Twenty-five soccer players (11 from a Category C team and 14 from a Category D team) participated in the study. Total energy intake was consistently below recommendations but increased on match days. Category C players consumed more protein and fat but fewer carbohydrates than Category D players, with significant differences on specific days (P<0.05). The Category D team showed greater adherence to macronutrient intake guidelines: protein (60.7% vs. 38.6%, P=0.023), fat (58.9% vs. 15.9%, P<0.0001), and carbohydrates (23.2% vs. 9.1%, P=0.053). NSKQ scores indicated poor nutritional knowledge in both teams, with no significant correlation between NSKQ scores and dietary adherence.

Conclusions: The dietary composition of the Category D team more closely aligned with reference guidelines compared to the Category C team. This discrepancy might reflect differences in dietary habits or nutritional misconceptions.

Background: Physical exercise is known to modulate arterial stiffness. However, this modulation can vary according to the type of exercise or training. This study aims to compare levels of arterial stiffness among healthy young men practicing different exercise modalities, including resistance training (RT), high-intensity cross-training (HICT), and running (RUN), and comparing these results with a control group.

Methods: Eighty healthy young men were divided into three exercise groups according to the type of exercise they practiced (RT, N.=20; HICT, N.=20; RUN, N.=20), plus a sedentary control group (CON, N.=20). In this observational study, participants were evaluated for arterial stiffness with carotid-femoral Pulse Wave Velocity (c-f PWV, m/s) and pulse wave analyses (Augmentation Index [Aix] and Augmentation Index normalized to a heart rate of 75 bpm [AIx@75bpm]). Participants were also assessed for cardiorespiratory fitness (VO2max, mL/kg/min) by means of maximal graded exercise testing.

Results: Despite the absence of statistical significance (P>0.05), the CON group showed less favorable arterial stiffness indices (AIx: 1.85±2.99; AIx@75bpm: -7.41±3.00) compared to all exercise groups ([RT AIx: -5.68±2.29; AIx@75bpm: -13.98±2.41]; [HICT AIx: -1.36±2.20; AIx@75bpm: -10.26±2.16]; [RUN AIx: -2.29±3.09; AIx@75bpm: -7.14±3.09]). The RUN group showed significantly higher VO2max than the other groups (RUN vs. CON, P<0.001; RUN vs. RT, P<0.001; and RUN vs. HICT, P<0.001).

Conclusions: The findings suggest that arterial stiffness does not differ according to different exercise modalities practiced by healthy young men.

Background: Health-related fitness (HRF) is essential for wellbeing and daily functioning. While objective fitness assessments are preferred, self-report measures are practical for large-scale or geographically diverse studies. Existing self-report HRF measures may lack sensitivity for younger or healthy adults. Additionally, many include items with no or poorly defined reference populations, potentially limiting their validity and comparability. This study examined the reliability and validity of single-item self-reported HRF measures of aerobic fitness, muscular strength and endurance, flexibility, coordination, agility, and body composition.

Methods: Between April and July 2023, University of Calgary students and staff (N.=129; mean age 28±9 years) completed the first questionnaire, with subsets completing a second questionnaire and validated fitness assessment. Nine items captured participants' self-rated HRF relative to those of the same age and gender. The nine self-reported HRF items were aggregated to obtain an estimate of overall HRF (Multidimensional Health-Related Fitness Scale, MHFS). We used intraclass correlations (ICC) to estimate test-retest reliability of the individual self-reported HRF items and MHFS. We assessed convergent validity with self-reported leisure physical activity (LPA) and concurrent validity with objective fitness measures using age- and sex-adjusted partial correlations.

Results: The single-item self-reported HRF measures (ICC=0.60-0.85) and MHFS (ICC=0.87) had acceptable test-retest reliability. The MHFS also had high internal consistency (Cronbach's α=0.87). Evidence of validity was observed with partial correlations ≥0.30 between self-reported HRF and LPA, and objective fitness measures.

Conclusions: The MHFS provides a reliable and valid HRF indicator among younger adult populations.