Journal of Sports Medicine and Physical Fitness最新文献

Background: Mass participation in amateur cycling events is popular, and ensuring participant safety is crucial. This study aimed to determine the epidemiology of medical encounters (MEs), including injury and illness, at mass-participation amateur cycling events and to explore associated risk factors.

Methods: We conducted a cross-sectional, descriptive, exploratory analysis of operational data collected during the 2015-2016 94.7 Ride Joburg cycling race. Outcomes include frequency (N., %), prevalence (%), incidence (injuries/1000 participants), did-not-finish (DNF, %), and Odds Ratio (OR, 95%CI).

Results: In total, 44849 individuals, mean age 40.06±11.68, participated in the 94.7 Ride Joburg cycling race during 2015-2016. We report the prevalence for MEs (5.3%) (injury: 1.7%, illness: 3.6%). The incidence of all MEs was 52.71 (50.61-54.88) (injury: 16.79 [15.61-18.03], illness: 35.92 [34.19-37.72]). Most race participants were male (79.0%), aged 31-50 (58.9%). Older age decreased the odds of injury, illness, or not finishing (P<0.001). Females had higher odds of injury (OR:1.43; 1.21-1.67; P<0.001) and for DNF (OR:1.57; 1.46-1.70; P<0.001) but lower odds of illness (OR:0.73; 0.64-0.64; P<0.001), compared to males. Overall, 7.9% of participants DNF, 6.9% had MEs, 3.2% were injured, and 3.8% were ill. Medical point location and distance were not significantly associated with medical encounters.

Conclusions: Older participants have lower odds of injury and illness encounters. Females have higher odds of injury encounters and not finishing the race but lower odds of illness encounters than males. These findings offer insights into injury and illness at mass-participation amateur cycling events.

Background: Although lactate threshold (LT) tests are widely used by athletes to evaluate endurance performance, such tests are not commonly applied in health controls among recreationally active subjects. This study aimed to investigate the test-retest reliability of walking as an exercise modality during LT testing and compare the test outcomes with those obtained during running.

Methods: Twenty-three male and female participants (25±3 year, 172±8 cm, 70±13 kg, and maximal oxygen consumption [VO2max] 51±5 mL·kg^-1·min^-1) performed four LT tests within 2-3 weeks, either using walking or running (two tests in each condition) protocols. The running tests were performed on a flat treadmill, and the pace increased by 1 km·h^-1 for each stage. During the walking tests, the pace was set to 6.5 km·h^-1, and the incline increased by 2.5% for each stage. LT was determined based on a fixed blood lactate concentration of 4.0 mmol·L^-1.

Results: Similar reliability values were observed for the walking and running protocol, and all between-trial differences were trivial or small. Significantly lower heart rate at LT was observed for the walking vs. running condition, but all between-modality differences were trivial or small. Analysis revealed that LT occurred at a slightly lower workload in walking than running (11.4±1.4 vs. 12.0±1.3 metabolic equivalents [METs]).

Conclusions: Given the trivial to small differences in LT variables observed between running and walking, these two protocols cannot be used interchangeably. However, the present study shows that walking represents an alternative exercise modality during LT testing in recreationally active subjects.

Background: This study aimed to analyze high pressing in open play during the 2021-2022 UEFA Champions League group stage (N.=192 matches).

Methods: The football pitch was divided into 18 zones, and the variables observed and analyzed included the pressing zone, pressing success, ball recovery zone, attack result, total passes until the outcome of play, team formations and ways used to counter the pressing. Statistical analysis was performed using the Chi-square Test, with significance set at P<0.05.

Results: Pressing occurred most frequently in front of the opposite goal post (P<0.001), while "Attack against organized defense," "Loss of possession," and "Throw-in won" were the most observed outcomes of play (P<0.001). The ball was recovered most of the time in the zones between the center line and the opponent's penalty area (P<0.001), and the teams mainly used long passes to counter the pressing (P<0.001). The most notable associations found are between: the pressing zone and the ball recovery zone (χ²=295.139, P<0.001), as well as the ways used to counter the pressing (χ²=148.723, P<0.001), the outcome of play and both the ball recovery zone (χ²=257.267, P<0.001) and the number of passes until the outcome of play (χ²=168.455, P<0.001).

Conclusions: Pressing in the offensive third seems to lead to ball recovery in the central third and attacks against an organized defense.

Background: Fastpitch softball participation continues to rise, yet there is minimal research into universal pitch count regulations for pitchers. The only current guidelines published by American Orthopaedic Society for Sports Medicine (AOSSM) in conjunction with the National Council for Youth Sports (NCYS), are based on pitch counts for youth baseball. The aim of this study was to quantify the total number of pitches thrown by high school fastpitch softball pitchers during a game outing to estimate the true workload experienced by the pitchers. We hypothesized that pitchers exceed the current recommendations.

Methods: Researchers collected total pitch count, quantified as total number of bullpens, warm-up (between inning), and in-game pitches thrown by high school varsity fastpitch softball pitchers during a single game outing.

Results: A total of 8248 pitches were counted during 89 varsity high school fastpitch softball pitcher outings. Of the 77 pitchers that pitched in a live game setting, 25.6% of pitchers pitched above the recommendation; which increased to 51.2% when including bullpen and warm-up pitches. Starters threw significantly more and relievers significantly less than the recommendations (P=0.001).

Conclusions: Though current pitch count recommendations for youth fastpitch softball, were modeled after current guidelines in youth baseball, they are all that exists to help softball pitchers from incurring increased workload. However, our data suggests that many fastpitch softball players pitch above the recommendation, and thus further research is required to determine injury association with pitch counts in fastpitch softball.

Background: The volume of physical activity (PA) is decreasing, including those types that would have an impact on bone mineral density (BMD). This leads to a search for suitable and accessible forms of PA with sufficient effects on BMD. CrossFit (CF) could be among these forms of PA. Exercises included in a CrossFit (CF) training program should contain stimuli that lead to bone mass remodeling and, therefore, could positively influence the development and maintenance of bone mineral density (BMD). However, the results verifying the effect of CF on BMD are inconsistent in the current studies. The aim of the study is to investigate the impact of CrossFit training with an average weekly volume of 511.3±124.4 and 202.5±34.2 minutes in middle-aged individuals on their BMD. Given the number of participants, this study is more of a case study.

Methods: This cross-sectional study included 36 males divided into three groups. Group G1 was inactive individuals who did not meet the WHO (2020) physical activity (PA) recommendations. Participants were from the 4HAIE project. Group G2 was CF recreational athletes and group G3 was CF competitive athletes. Participants G2 and G3 had been doing regular CF training for at least 2 years. The average duration of training in G2 was 4.0±2.1 years and in G3 5.9±2.4 years. The age of the participants ranged from 26 to 35 years (G1 31.3±2.5, G2 31.9±2.5, G3 29.9±2.3 years). BMD was measured using DXA.

Results: The results showed that although the G2 group had higher BMD values than G1, the differences were not significant; the P values ranged from 0.180 to 0.617. The G3 group had significantly higher BMD values than G1 and G2. When comparing G3 and G2, the P values ranged from 0.000 to 0.048, while the difference in the lower limbs was not significant (P=0.053 and 0.146). When comparing G3 and G1, the P values ranged from 0.000 to 0.002.

Conclusions: Therefore, we can conclude that CF could have a positive effect on BMD, but only if training is performed over a long period and at a high volume, which aligns with the level of PA recommendations for additional health benefits (more than 300 min/week moderate-intensity, or 150 min/week vigorous-intensity) according to the WHO.

Background: Concussion baseline testing is standard practice in collegiate athletes. The influence of concussion history on balance performance remains pervasive, especially with computerized, quantified measures. The aim of this study was to explore concussion history on baseline balance measures.

Methods: A total of 175 division I football and men's lacrosse players (height = 182.6±5.6 cm, weight = 91.7±15.4 kg, age = 19.8±1.2 years) performed the Stability Evaluation Test (SET) on the VSR Sport by NeuroCom^®.

Results: There were no significant differences between those with a positive and negative concussion history on the seven balance measurements. There were significant differences between sports with lacrosse players reporting lower sway velocities on the double leg firm (P=0.001), tandem firm (P=0.003), double leg foam (P=0.002), single-leg foam (P<0.001), and total composite score (P=0.002).

Conclusions: A previous history of a concussion does not appear to influence velocity sway measures. Velocity sway measures may differ between various collegiate teams.

Background: This study examined the sex-related variation in the developmental changes of growth and physical fitness outputs in young Brazilian basketball players.

Methods: The study included repeated measures of 90 players (46 females and 44 males), aged between 9.5 and 19.5 years. Performance assessment included the countermovement jump, line-drill test, and yoyo intermittent recovery test level-1. With a mixed-longitudinal design, athletes were measured at least 2 times over 12 months and a maximum of 36 months. Bayesian hierarchical models were used to model developmental trends across adolescence.

Results: Our model-based predictions indicate substantial differences in the rate of development of both vertical jump and line-drill test performances and performance development leveling off. Female players' maximal short-term performance rate of development was lower, and a plateau in improvements was attained earlier than male players. There was substantial variation in the rate of development of intermittent endurance between females and males, which became clear when intermittent endurance development was adjusted for body size in the model, particularly for female players.

Conclusions: These findings offer valuable insights to youth basketball coaches when interpreting the asynchrony in growth and physical fitness progression during adolescence.

Background: CrossFit training, which includes functional exercises and improves various physical parameters, has become increasingly popular in recent years. Since CrossFit is a high-intensity training program, injury rate and risk factors must be evaluated. This study aims to determine the relationship between the Functional Movement Screen (FMS) score and balance, core endurance, and musculoskeletal system injuries in CrossFit athletes.

Methods: This cross-sectional study included 52 CrossFit athletes. FMS assessed biomechanical abnormalities, fundamental movement patterns, and asymmetries in CrossFit athletes. Four different tests (trunk flexion, Biering Sorenson, lateral plank, and plank) with different positions were used to evaluate core endurance. The Y balance test was used to assess dynamic balance.

Results: The mean age of the 52 participants (21 female, 31 male) was 28.02±8.64 years, and their mean body mass index was 24.69±4.09 kg/m². The lumbar spine was the most commonly injured body part (19%), and the thoracic spine and knee were second (13%), followed by the knee and shoulder (10%). A relationship was found between injury and FMS composite (r=-0.338; P=0.014), deep squat (r=0.31; P=0.026), shoulder mobility (r=0.329; P=0.017), and rotary stability score (r=-0.297; P=0.032).

Conclusions: New screening tools such as FMS are essential in determining movement quality and its relationship with injury prevention and performance predictability. In addition, this study will guide corrective exercise programs drawn by physiotherapists according to the movement pattern determined by the screening results and safe and practical recommendations to prevent injuries.

Background: This study assessed the influence of knee and ankle muscle strength and endurance on lower extremity injury patterns (Injury incidence rate, injury type, and return-to-sport period) in elite taekwondo athletes.

Methods: The study involved 60 elite taekwondo athletes (male and female 30, respectively) aged 18 and older, who trained intensively at a training institution for two years, from January 2022 to December 2023. The injury incidence rate per 1000 hours of training was calculated using a 95% Poisson confidence interval. We also employed simple linear regression analysis to identify the factors that muscle strength and endurance affect injury. All statistical significance levels were set at α=0.05, and we used SPSS version 27.0 for Windows for our analysis.

Results: In both male and female Taekwondo athletes, there was no significant association between the injury incidence rate of lower extremity and the muscle strength and endurance of the knee and ankle. However, the ratio of muscle endurance to the agonist and antagonist muscles in the knee and ankle was found to be associated with lower extremity injury incidence rates. This is also associated with ligament injury incidence rates.

Conclusions: Effectively managing lower extremity injuries in taekwondo athletes necessitates a proper balance of muscle endurance between the agonist and antagonist muscles in the knee and ankle. Therefore, it is essential to develop an exercise program that addresses the imbalance between these muscle groups for taekwondo athletes.

Background: Over the past several decades, soccer has undergone significant evolution, reflected by increasing physical demands and distinct anthropometric characteristics among elite players worldwide. This study examines long-term trends in anthropometric and physiological characteristics of professional soccer players of Greece first division from 1981 to 2013.

Methods: A repeated cross-sectional study was conducted, analyzing data from 850 male players, aged 18-40, competing in Greece's top soccer league. Participants were divided into five groups based on evaluation periods (1981-1989, 1990-1995, 2000-2004, 2005-2010, and 2011-2013). Anthropometric measurements included height, body mass, and body fat percentage, while physiological assessments included maximal oxygen uptake (V̇O2max), minute ventilation (VE), anaerobic power (Wingate Test), and vertical jump height (countermovement jump, CMJ). Data were analyzed using non-parametric statistical tests, with correlations assessed and adjusted for anthropometrics.

Results: Over time, significant increases were observed in height (η²=0.089, P<0.001), V̇O2max (η²=0.281, P<0.001), anaerobic power output (η²=0.732, P<0.001), and CMJ height (η²=0.160, P<0.001), while body fat percentage declined significantly (η²=0.085, P<0.001) from 1981 to 2013. Positive correlations were found between V̇O2max, anaerobic power, and CMJ performance.

Conclusions: The observed improvements in anthropometric and physiological characteristics among Greek soccer players reflect the increased physical demands of modern soccer over a period of about 30 years. Increased aerobic and anaerobic capacities, along with improved body composition, indicate the impact of advancements in training and selection practices. Future research should investigate how various training practices and individual internal and external factors affect performance outcomes.