International journal of exercise science最新文献

Fitness testing is employed by some law enforcement agencies to assure performance in occupational tasks. The aim of this study was to investigate associations between musculoskeletal fitness assessment scores and performance in police occupational tasks. Retrospective data from 106 law enforcement officers who completed five musculoskeletal fitness assessments (vertical jump (VJ), hand grip strength, leg back dynamometer, 1-minute push-ups and sit-ups) and three routine occupational tasks (1.22m fence jump (FJ), 8.5m victim drag (VD) with 101kg and a get-up (GU)) were collected. A standard multiple regression was performed to determine if the results in fitness assessments were predictive of performance in the occupational tasks. Models combining all fitness assessments significantly predicted performance in FJ (F(5,88)=12.228, p<0.001; adjusted R²=0.38), VD (F(5,88)=9.407, p<0.001; adjusted R²=0.31) and GU (F(5,87)=14.319, p<0.001; adjusted R²=0.42). Further analysis of individual predictors highlighted that performance in the VJ test was a significant contributor for all models, uniquely predicting 15% of FJ (p<0.001), 4% of VD (p=0.03) and 8% of GU (p=0.001) performance. Grip strength uniquely contributed 3% to performance in the VD (p=0.05) and performance in the sit-up test contributed 8% to GU performance (p=0.001). Performance in police-specific occupational tasks requires a combination of muscular strength, power, and endurance. These musculoskeletal fitness components should be ideally assessed in recruitment and return-to work practices to ensure officers can safely and optimally perform their occupational requirements.

The purpose of the study was to determine the prevalence of sudden cardiac arrest (SCA) risk factors in high school (HS) athletes. Thirty-three male soccer players from a public HS in the southeastern United States (ages 14-17) self-reported survey data. Participants reported demographic, lifestyle, heart health, COVID-19 history, and symptoms indicative of SCA risk. An electrocardiogram (ECG) assessed heart rate (HR), rhythm, and electrical activity. Resting HR and blood pressure (BP) were measured with a BP monitor. The association between COVID-19 history, HR, and BP were calculated. Participants were divided into ECG groups (normal or abnormal). Independent t-tests assessed comparisons between groups to identify SCA risk. Over 50% of participants (n=17) reported experiencing shortness of breath (SOB) and 30% (n=10) reported chest pain. A history of chest pain was associated with abnormal ECGs (p<0.04). Thirteen (39.4%) participants reported a COVID-19 history. Of these, 5 presented with persisting symptoms, 2 with elevated HR, and 3 with elevated BP. Eleven (33.3%) participants had an abnormal ECG and of these eleven, 8 (72.7%) reported a positive COVID-19 history (p<0.01). The current American Heart Association suggested screening method is limited. An ECG should be used in preparticipation screenings (PPS) and return to participation (RTP) decisions for athletes with a COVID-19 history. Family cardiac history, chest pain during exercise, and an abnormal QRS interval should be used to identify SCA risk.

The purpose of this study was to analyze the impact of Latin ballroom dance training on gait biomechanics, anxiety, and depression. There were twelve Latin ballroom dancers and twelve recreationally active non-dancers that participated in this research. For collecting data on gait biomechanics, participants walked on a pressure sensitive walkway system and force plates to collect information on foot and ground interactions. Reflective trackers were placed on the anterior part of their hips, knees, and ankles to measure frontal plane lower leg alignment during weight acceptance. A survey including the Generalized Anxiety Disorder-7 (GAD-7) assessment, Patient Health Questionnaire-9 (PHQ-9) assessment, and questions developed by the researchers were used to collect psychological data. Data was analyzed using independent t-tests, one-way ANOVA, chi-squared tests, and contingency tests. Results in this study showed that Latin ballroom dancers were minimally different in their gait biomechanics when compared to the non-dancers. The only statistically significant differences in the absolute value difference between legs for peak braking impulse (p=0.04) and the difference from left to right leg in peak braking ground reaction forces (p=0.05). All other variables of gait biomechanics that were measured in this study showed no statistically significant differences between the 2 groups (p>0.05). Dancers showed higher levels of anxiety, with 58.33% of dancers having a probable anxiety disorder and 8.33% of non-dancers having a probable anxiety disorder (p=0.06). However, there was no statistically significant difference between dancers and non-dancers and their likelihood of a depression diagnosis (p=0.16). Furthermore, there were differences in when dancers experienced symptoms when compared to non-dancers. Coaches and dancers should be aware of any positive or negative effects of Latin ballroom dance training on anxiety and depression so that they can make educated decisions to facilitate and promote health, safety, and wellness among dancers.

The International Journal of Exercise Science (IJES) Working Group for Opportunity, Representation, and Diverse Perspectives was tasked with developing a position stand to provide guidance in critical areas of inclusion. We present to authors, reviewers, and all readership IJES ideals to utilize in practice. Key points are presented, followed by a deeper look with greater explanation into the areas of inclusive language, diversity and inclusion in research, and accessibility. The same approach is presented for the areas of age, disability status, gender identity and sexual orientation, race, and ethnicity with attention to Indigenous Communities, religion, socioeconomic status, and neurodiversity. Person-first language is encouraged, with the acknowledgment that the preference of different community members may vary. IJES is committed to maintaining an environment that is welcoming to all identities so that they feel valued, respected, and included.

Heart rate variability (HRV) is used as a measure of autonomic nervous system (ANS) function and is based on heart rate (HR) beat-to-beat time interval variance analysis. Various techniques are used for recording HR, however, few studies have compared Holter-type recordings vs HR monitors (HRM) during an orthostatic challenge.

Objectives: Compare HRV measures from an electrocardiogram (ECG) Holter and a HRM as a tool for investigating ANS response for post-concussion rehabilitation follow-up.

Methods: Twenty-seven participants (n = 27; 15 females, 12 males), 18 to 35 years old, non-smoking, no history of cardiac illness and physically active (3 times per week, 60 mins, moderate intensity exercise) participated in the study. ECG signals and HRM were recorded beat-to-beat (R-R) simultaneously. A motorized tilt table was set at 0 degree for supine and 85 degrees for standing position. Participants were instructed to remain for 7 minutes in each position. R-R signals from both Holter and Polar HRM recording starting points were matched before further analysis. Bland-Altman plots were used to compare recordings from the Holter (gold standard) and the Polar HRM in both positions. Unpaired t-test was used to compare measurements obtained with both systems. Significance was set at p < 0.05.

Results: No significant differences were observed between R-R measurements taken with both systems under equal conditions (supine and standing). Same variables under similar conditions were significantly correlated (p = 0.0001).

Conclusion: Both recording and analysis systems (Holter vs HRM) yielded comparable results. Thus, both systems appear valid and interchangeable for HRV analysis for measuring orthostatic challenge HRV responses.

A negative association between physical activity and depressive symptoms is consistently reported within scientific literature and physical self-concept has been suggested to mediate this pathway. However, for whom these associations are strongest remains poorly understood, and little is known about how other psychosocial factors might be implicated. Consequently, we examined how various exercise motivations, specifically appearance, physical health, and mental health, might moderate the indirect effect of physical activity on depressive symptoms through physical self-concept. Canadian young adults (N = 496, Mage = 20.36, SD = 1.87) completed an online questionnaire. Mediation and moderated-mediation models were tested using PROCESS macro in RStudio. A significant indirect effect (ß = -0.18, CI [-0.005, -0.003]) of physical activity on depressive symptoms through physical self-concept was found. Exercise motivations moderated the association between physical activity and physical self-concept, such that the association was stronger when individuals were motivated by physical health. Thus, the effect of physical activity on depressive symptoms varied according to physical self-concept and physical health-exercise motivations. We conclude that motivation should be considered when developing and delivering physical activity prevention efforts for depressive symptoms.

Basketball players are prone to ankle injuries. It is unclear if wearing ankle compression garments (CGs) can enhance balance control and time to fatigue in those athletes. The purpose of this study was to examine the impact of ankle CGs on both time to fatigue and single-leg balance. Sixteen Division II (D2) collegiate basketball players participated in the study. The Cumberland Ankle Instability Tool (CAIT) was used to assess ankle stability. Fatigue was induced through deficit heel raises, and single-leg balance was assessed with the Athletic Single Leg Stability Test (ASLST) of the Biodex Balance System. Ten out of 16 (62.5%) basketball players were classified as having chronic ankle instability (CAI). Wearing CGs did not significantly prolong the time to fatigue (P = .774), and participants with CAI and without CAI had a similar time to fatigue (P = .958). In addition, wearing CGs significantly worsened single-leg balance before fatigue (P = .021), but enhanced balance control after fatigue (P = .027). Results indicate a strong prevalence of CAI in collegiate basketball players, and wearing CGs may not be able to enhance single-leg balance before fatigue. Although participants who wore CGs did not significantly increase their time to fatigue, their single-leg balance significantly improved after fatigue. This finding suggests wearing ankle CGs may have the potential to remediate the impact of fatigue on balance control. Future studies with a larger sample size are needed to further examine the impact of wearing ankle CGs on fatigue and single-leg balance.

This study aimed to analyze the effect of box height on box jump performance among recreationally active college students. Fourteen males (age = 20.8 ± 4.1 years, height = 178.3 ± 6.3 cm, weight = 82.3 ± 13.0 kg) and seventeen females (age = 20.8 ± 2.1 years, height = 167.1 ± 5.5 cm, weight = 64.5 ± 7.4 kg) completed box jumps at five different box heights that corresponded to 0, 20, 40, 60, and 80% of their maximal box jump height. Variables of interest included peak force, rate of force development, peak rate of force development, peak power, velocity at peak power, jump height, time to take-off, and reactive strength index modified. Peak force at 80% maximal box jump was significantly higher than 0% in the female cohort (p = 0.001). No significant differences for any of the other variables were observed in males, or at any other height lower than the 80% maximal box jump height for females (p > 0.05). Overall, variations in box height did not influence box jump performance in recreationally trained individuals when the intent to perform a maximal-effort jump was emphasized. This is important for strength and conditioning coaches and trainers, as they can utilize boxes of varied heights when teaching proper landing techniques to novice athletes with no decrements in propulsive performance.

The overhead squat, as part of the Functional Movement Screen (FMS), can analyze total- and lower-body mechanics. Shoulder taps, which incorporates a push-up position and challenges shoulder, trunk, and hip stability, may identify movement deficiencies indicated by multiple FMS actions which could be useful for law enforcement recruits. This study determined overhead squat and shoulder taps relationships, associations between these screens with body composition and fitness, and differences in body composition and fitness according to overhead squat/shoulder taps scores in recruits by sex. Retrospective analysis was conducted on 202 recruit datasets (158 males, 44 females), which included: overhead squat and shoulder taps scores; age, height, and body mass; skeletal muscle (SMM%) and body fat mass (BFM%) percentage; waist-to-hip ratio; grip strength; 60-s push-ups and sit-ups; 75-yard pursuit run; vertical jump; medicine ball throw; and multistage fitness test (MSFT). Spearman's correlations (p<0.05) determined relationships between the overhead squat and shoulder taps, and between the screens and other variables. Kruskall-Wallis H tests compared the variables when recruits were split into groups based on overhead squat/shoulder taps scores. A significant correlation was found between the screens for male (ρ=0.231) but not female (ρ=0.258) recruits. Overhead squat score had a moderate relationship with BFM% in females (ρ=-0.312). Shoulder taps had a small relationship with SMM% in males (ρ=0.163). There were no differences in body composition and fitness when recruits were split based on screen scores (p=0.086-0.994). While morphology may influence movement screen performance, the screens had minimal capacity for associating movement deficiencies to fitness.

This study aimed to investigate the effects of chronic β-alanine (βA) plus acute sodium bicarbonate (SB) co-supplementation on neuromuscular fatigue during high-intensity intermittent efforts in swimming. Eleven regional and national competitive-level young swimmers performed a neuromuscular fatigue assessment before and immediately after two 20 × 25-m front crawl maximal efforts every 90 s, performed at pre- and post-4-week co-supplementation. Neuromuscular fatigue was evaluated by percutaneous electrical stimuli through the twitch interpolation technique on the triceps brachii and quadriceps femoris. Performance was defined by the mean time of the 20 efforts and blood samples to lactate concentrations were collected every four efforts. Participants supplemented 3.2-6.4 g·day^-1 of chronic βA or placebo (PL) during four weeks, and acute 0.3 g·kg^-1 of SB or PL 60 min before the second assessment (allowing βA+SB and PL+PL groups). No statistical changes were found in neuromuscular fatigue of triceps brachii. In the quadriceps femoris, a main effect of time was found in potentiated twitch delta values in pooled groups, showing a statistical increase of 19.01% after four weeks (Δ = 13.05 [0.35-25.75] N; p = 0.044), without time × group interactions. No statistical difference was found in the swimming performance. Blood lactate increased by 25.06% only in the βA+SB group (Δ = 6.40 [4.62-8.18] mM; p _Bonf < 0.001) after the supplementation period. In conclusion, 4-week βA and SB co-supplementation were not able to reduce neuromuscular fatigue levels and improve performance in highintensity intermittent efforts, but statistically increased blood lactate levels.