Journal of Sports Medicine and Physical Fitness最新文献

Introduction: The aim of this study was to systematically evaluate the effects of blood flow restriction combined with aerobic exercise on aerobic capacity, lower limb muscle strength and mass in healthy adults.

Evidence acquisition: According to PRISMA's statement, we searched Web of science, Medline, Embase, Cochrane library, CNKI, Wan fang, and VIP databases to collect randomized controlled trials on the effects of aerobic exercise with blood flow restriction on improving aerobic capacity, lower limb muscle strength, and muscle mass in healthy adults. The studies were published from the establishment of the database to November 2023. A supplementary search has been conducted on March 8, 2024. Review Manager5.3 and Stata17 were used for statistical analysis.

Evidence synthesis: A total of 16 RCTs with 388 participants were included. The results of meta-analysis showed: Aerobic exercise with BFR significantly affected aerobic capacity (MD and 95%CI 1.06[0.29,1.83], P<0.05), lower limb muscle strength (MD and 95%CI 7.56[5.80,9.33], P<0.05) and lower limb muscle mass (MD and 95%CI were 3.02[1.63,4.42], P<0.05) in healthy adults. The results of subgroup analysis showed that intermittent pressure was better than continuous pressure (P<0.05). Compared with the elderly, the effect of young and middle-aged was better (P<0.05). At the same time, the training form using power bikes is better than walking or running. Finally, 2-6 weeks, 2-3 sessions per week, 10-45 minutes per session can effectively improve the aerobic capacity of healthy adults.

Conclusions: Aerobic exercise with BFR can significantly improve aerobic capacity, lower limb muscle strength and mass in healthy adults. In the future, the effects of blood flow restriction training on healthy adults should be further studied, and the form of pressure, intervention cycle, frequency, time, intensity and other variables should be further controlled.

Background: The available evidence on the impact of altitude training on sports performance is inconclusive. Heart rate variability (HRV) and heart rate recovery (HRR) are among the most frequently used parameters in athletic performance analysis and monitoring. Our study aims to investigate the effect of high altitude training on HRR and HRV, which are reliable predictors of athletic performance.

Methods: Elite national swimmers were included in the study. Time domain and frequency domain analyzes were performed with the Polar Verity Sense device and Kubios HRV software. HRR were measured at one-minute intervals for the first 15 minutes after peak heart rate, and then recorded at the 20^th, 25^th and 30^th minutes.

Results: A significant difference is observed from the beginning to the 11^th minute. The P value at 1, 3, 5, 7 and 11 minutes is 0.001, 0.023, 0.032, 0.019 and 0.020, respectively. Similarly, a significant change was observed in delta HRR. Among the HRV parameters, RMSSD, SDNN, Poincaré SD1 and PNS are statistically significant. P values are 0.004, 0.018, 0.024 and 0.013 respectively.

Conclusions: High altitude training program has a positive effect on HRV and CRV in elite swimmers. This condition is associated with increased cardiac parasympathetic activity. Time domain analyses have proven to be more beneficial for HRV. HRR and HRV are effective, reliable and inexpensive methods of performance monitoring of elite athletes.

Background: Due to the change in field hockey match format, the need exits for research to determine whether current fitness test are still valid indicators of match performance. This study aimed to determine the direct validity of the 5-m multistage shuttle test (5-m MST) and Yo-Yo Intermittent recovery level 1 test (Yo-Yo IR1) by correlating their results with external load measures in international field hockey matches.

Methods: Nineteen female field hockey players completed the 5-m MST and Yo-Yo IR1 before nine matches.

Results: Players covered mean distances of 750.3 m±19.6 m (5-m MST) and 1649.7 m±277.6 m (Yo-Yo IR1). Average relative distance, relative player load, and high-intensity activity during matches were 107.8±16.3 m/min, 10.3±1.4 AU/min, and 10.0±3.0%, respectively. The 5-m MST showed small to moderate significant (P<0.05; r=0.21-0.5) correlations with relative distance and high-intensity activity, while the Yo-Yo IR1 only had a small negative significant (P<0.05; r=-0.27) correlation with high-intensity activity. Strong correlations (r>0.51) were found between the 5-m MST and Yo-Yo IR1.

Conclusions: The tests demonstrated low direct validity for current field hockey matches due to weak relationships with relative load and running performance. Additionally, the strong correlation between the Yo-Yo IR1 and 5-m MST suggests that both tests may not be necessary to assess match readiness. Coaches should consider using better-validated fitness tests for this population and sport.

Background: The aim of this study is to evaluate the influence of implementation of the BFR training on the hypertrophy and strength of the lower limb muscles in combat sports fighters, using common and easy to perform both training and control methods.

Methods: Design as a randomized control trial (RCT). The study included 30 men, MMA fighters since at least a year. They were divided into two groups: (A, a control group; B, men with the BFR training). The training lasted 8 weeks (3 times a week) and consisted of performing a set of specific exercises with a load of 20% 1RM.

Results: The Wilcoxon analyzing test showed important changes in muscle girth (P<0.01) and lower limb muscular strength (P<0.05). These changes were to be seen in the tested group only, not in the control group.

Conclusions: Occlusion training is effective in increasing strength and hypertrophy of lower limb muscles in martial arts fighters.

The bicuspid aortic valve (BAV) is the most common congenital heart defect among adults, often leading to severe valve dysfunction and aortic complications. Despite its clinical significance, uncertainties persist regarding the impact of sports participation on the natural course of BAV disease. The SPREAD (Sport PRactice and its Effects on Bicuspid Aortic valve Disease) study is a multicenter and multinational project designed to investigate this relationship. This paper outlines the study's design, and objectives. The study is divided into two phases; phase one involves a cross-sectional analysis comparing aortic dimensions and valve function among competitive athletes with BAV, athletes with tricuspid aortic valves (TAV), and sedentary individuals with BAV. The second phase is a prospective, longitudinal follow-up aiming to evaluate the impact of regular sports training on disease progression. The SPREAD study seeks to provide evidence-based insights into the effects of sports participation on BAV disease progression, guiding clinical decision-making regarding sports eligibility and risk stratification for individuals with BAV.

Background: This study investigates if countries are more focused on certain specializations (one day, climb, sprint, time trial [TT] and grand tour [GC]) in male professional road cycling and if this is possibly linked to the countries landscape (for example, does a mountainous country have more climbers?) and anthropometric characteristics (does the mountainous country also have lighter cyclists?) of their cyclists.

Methods: Body weight, height, procyclingstats (PCS) points per specialty were gathered from 1810 professional cyclists out of 15 countries, as well as the elevation span of those countries. To compare the anthropometric differences between different countries, height was normalized based on the average height of the countries' population, while BMI was used as a correction for body weight.

Results: The average anthropometrics (body weight and height) of professional cyclists in a country are related to the relative number of PCS points collected in GC, sprint and climb races. This means that when a country has shorter and lighter cyclists, they score relatively better in GC and climb races and vice versa for sprint races, which indicates that countries are focused on certain specialties. However, these relationships were not found for TT and one day PCS points. In addition, countries with larger cyclists have a less mountainous (elevation span) landscape compared to countries with lighter cyclists.

Conclusions: The results suggest a selection bias towards smaller/lighter or taller/heavier cyclists in various countries, probably caused by the terrain of their home country, leading to missed opportunities for some cyclists to reach professional level.

Background: The risk of injury in rugby is high, due to the contact nature of the game. Players are constantly exposed to impact and collision during training and match-play. Rugby union consists of various risk factors that predispose players to injury. The aim of the study was to determine the risk factors of injury and to predict the risk of injury per playing position during match-play.

Methods: The study followed a quantitative, non-experimental, and cross-sectional research design. A total of 252 male rugby players, aged 18 to 20 years, who played in a collegiate rugby competition in South Africa (SA) for the 2022 season were conveniently sampled for the study. The playing position, time of injury (whether during a match or training), use of protective equipment, and phase of play in which the injury occurred were recorded. Injury data was captured by qualified healthcare professionals using an adapted injury surveillance questionnaire.

Results: The study found that potential risk factors for injury included illegal or dangerous play, playing in the second half of the match (more specifically the third quarter of the match), and playing in the offensive part of the field (more specifically between the opposition-22 and halfway line). Contact events were the most common cause of match injury (91.1%). The half of the match in which an injury was sustained was significantly different between forwards and backs (P=0.011). A statistically significant association was found between playing position and the phase of play in which injury was sustained (P=0.021). Regression analysis showed that playing between the opposition-22 m line and the halfway line was a significant predictor of injury for both forwards and backs (P=0.035).

Conclusions: In conclusion, potential risk factors for injury were related to dangerous play, time during the match (specifically the third quarter of the match), and location of play (specifically between the opposition-22 m line and halfway line). The area of play was a significant predictor of injury for all players. It is recommended that greater efforts in collecting epidemiological data need to be made to broaden the knowledge base on injuries and provide strategies to coaches and players to reduce the risk of injury in rugby.

Background: Non-alcoholic fatty liver disease (NAFLD), linked to sedentary lifestyles and metabolic dysfunction, is highly prevalent. Exercise is an established intervention, but the relative efficacy of different exercise modalities remains unclear. The aim of this study was to compare the effects of moderate-intensity continuous aerobic training and High-Intensity Interval Training (HIIT) on physical fitness, biochemical parameters, and liver function in NAFLD patients.

Methods: Sixty NAFLD patients (32 males, 28 females; age: 49.7±8.7 years; BMI: 31.1±3.3 kg/m²) were randomized into HIIT, aerobic training, and control cohorts. The HIIT cohort performed 4-minute high-intensity intervals at 85-95% of peak heart rate, interspersed with 3-minute active recovery at 60-70% of peak heart rate for 30-40 minutes per session. The aerobic training cohort performed continuous exercise at 60-70% of peak heart rate for 45-60 minutes per session. Both intervention cohorts underwent 12 weeks of supervised training, thrice weekly. Before and after the intervention, assessments included cardiorespiratory fitness, muscular strength, flexibility, lipid profile, liver enzymes, inflammatory markers, insulin sensitivity, and oxidative stress markers.

Results: Compared to controls, both exercise cohorts showed significant improvements in cardiorespiratory fitness, muscular strength, and flexibility. However, HIIT elicited superior enhancements in cardiorespiratory fitness and muscular strength. Biochemically, both exercise cohorts exhibited reductions in triglycerides, low-density lipoprotein (LDL) cholesterol, liver enzymes (alanine aminotransferase [ALT], aspartate aminotransferase [AST]), inflammatory markers (C-reactive protein [CRP], interleukin-6 [IL-6]), insulin resistance (homeostatic model assessment of insulin resistance [HOMA-IR]), and oxidative stress markers (malondialdehyde [MDA], protein carbonyl). Notably, HIIT yielded more substantial improvements in these parameters.

Conclusions: HIIT and traditional aerobic training are effective in improving physical fitness and ameliorating biochemical indicators in NAFLD patients. Notably, HIIT appears to be more advantageous in enhancing cardiorespiratory fitness, muscular strength, and metabolic, inflammatory, and oxidative stress profiles, suggesting its potential as a time-efficient and effective exercise modality for managing NAFLD.

Cardiorespiratory fitness (CRF) has been increasingly recognized in recent years as an important predictor of risk for adverse outcomes in numerous chronic conditions. In fact, a growing body of epidemiological and clinical evidence demonstrates that CRF is a potentially stronger predictor of mortality than established risk factors such as smoking, hypertension, hyperlipidemia, and type 2 diabetes. Moreover, adding CRF to these traditional risk factors significantly improves the reclassification of risk for adverse outcomes. The utility of CRF now extends far beyond all-cause and cardiovascular mortality to include the prevention and treatment of numerous other chronic conditions; CRF has been demonstrated to have a mitigating influence in as many as 40 such conditions. Herein we discuss the impact of CRF in the prevention of chronic disease in both adults and children. This discussion includes recent data on interactions between CRF and aging, obesity, statin use, incidence of diabetes, and the impact of CRF and physical activity patterns in adolescents including mental health, scholastic achievement, and cardiometabolic health. Finally, we discuss how CRF, as an essential vital sign, can be implemented in clinical practice.

Background: The aim of this study was to investigate the effects of facial cooling on physiological and perceptual responses during a simulated fencing competition.

Methods: Using a randomized, crossover design, six competitive male fencers completed two trials of seven simulated fencing matches. Each match consisted of 22×10 s bouts of high-intensity fencing movements. Static rest (12 s) separated each bout, with 60-second rest after bouts seven and 14, during which, in the experimental condition, participants were sprayed with a facial water mist and fanned.

Results: Relative to control, facial cooling reduced tympanic temperature (mean difference [MD]: 0.2±0.03 °C; 95% likely range [CL95]: 0.13-0.3 °C), heart rate (MD: 12±3 b·min^-1; CL95: 5-20 b·min^-1), and ratings of perceived exertion (RPE) for the dominant arm (MD: 2±0; CL95: 1-3), legs (MD: 2±0; CL95: 1-3), and total exertion (MD: 2±0; CL95: 1-3). Moreover, the benefits of facial cooling on RPE of the dominant arm and legs were magnified as the competition progressed. Facial cooling also improved ratings of perceived thermal comfort and perceived thermal strain.

Conclusions: While the performance benefits of the intervention require exploration, facial misting positively affects both physiological and perceptual responses during fencing.