American Journal of Sports Science and Medicine最新文献

{"title":"Against Negative Splitting: The Case for a Counterintuitive Pacing Strategy for Elite Marathon Athletes in Official Events","authors":"G. Fernandes, Victor Maldonado","doi":"10.12691/ajssm-12-1-1","DOIUrl":"https://doi.org/10.12691/ajssm-12-1-1","url":null,"abstract":"","PeriodicalId":261831,"journal":{"name":"American Journal of Sports Science and Medicine","volume":"38 04","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139683646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Association between depressive symptoms and episodes of musculoskeletal injuries in Brazilian athletes during crisis time","authors":"Lucas Rafael Lopes, Giuliana Rodrigues de Souza, Rodrigo Araujo Goes, Marcus Vinicius Galvão Amaral, João Antonio Matheus Guimarães, Victor Rodrigues Amaral Cossich, Jamila Alessandra Perini","doi":"10.12691/ajssm-11-1-3","DOIUrl":"https://doi.org/10.12691/ajssm-11-1-3","url":null,"abstract":"The crisis time generated negative impacts in sports. This study aimed to investigate the main psychological symptoms and the resilience profile of Brazilian athletes during the COVID-19 pandemic. A cross-sectional observational study was conducted, involving 474 athletes from different sports, who completed an online self-reported questionnaire about their sociodemographic and sports profile, COVID-19 clinical profile, life and health habits, profile psychological and resilience. A total of the 441 athletes (93%) reported some impairment of mental health: 81% concern, 68% stress, 63% mood change, 61% anxiety, 50% insomnia, 48% pessimism, 47% fear, 40% sadness, 13% depression, and 7% panic. The lower family income was associated with concern ( p =0.02), insomnia ( p =0.05), fear ( p =0.05) and sadness ( p =0.05). The depression was associated with lower family income (OR=3.7 CI95%=1.4-9.5), changes in financial income (OR=2 CI95%=1.1-3.8), not able to adapt training (OR=2.8 CI95%=1.5-5.0), and musculoskeletal injuries (OR=2.6 CI95%=1.1-3.8). The mean resilience score in all athletes was 130±14 points and the group with a low resilience score (up to 125 points) showed more anxiety, pessimism, concern, depression, fear, insomnia, mood change, panic, sadness, and stress. The score decreased by 1.6 points according to the cumulative psychological outcome ( p <0.01). The years of sports practice and weekly training hours were associated with higher resilience scores (above 140 points). The identification of factors associated with the presence of negative psychological symptoms and the resilience of athletes can help monitor post-pandemic mental health, promoting the well-being and quality of life of these individuals, optimizing sports performance, and mitigating the occurrence of injuries","PeriodicalId":261831,"journal":{"name":"American Journal of Sports Science and Medicine","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123491161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Torque and Neuromuscular Responses are not Joint Angle Dependent During a Sustained, Isometric Task Anchored to a High Perceptual Intensity","authors":"Robert W. Smith, Terry J. Housh, John Paul V. Anders, Tyler J. Neltner, Jocelyn E. Arnett, Dolores G. Ortega, Richard J. Schmidt, Glen O. Johnson","doi":"10.12691/ajssm-10-2-1","DOIUrl":"https://doi.org/10.12691/ajssm-10-2-1","url":null,"abstract":"","PeriodicalId":261831,"journal":{"name":"American Journal of Sports Science and Medicine","volume":"278 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122919361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Positional Differences in External Load in Professional Male Volleyball Players","authors":"Damjana V. Cabarkapa, D. Cabarkapa, Andrew C. Fry","doi":"10.12691/ajssm-10-1-5","DOIUrl":"https://doi.org/10.12691/ajssm-10-1-5","url":null,"abstract":"","PeriodicalId":261831,"journal":{"name":"American Journal of Sports Science and Medicine","volume":"184 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134461758","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antropometric Characteristics Structure of “VC Jahorina” Pale Volleyball Players","authors":"R. Pavlović, Vladan Savić, Danilo Tadić, Ljubo Milićević","doi":"10.12691/ajssm-10-1-4","DOIUrl":"https://doi.org/10.12691/ajssm-10-1-4","url":null,"abstract":"Background: Morphological dimensions represent the functioning of the growth and development of the musculoskeletal system and also play a role in specific volleyball activities. In the sphere of volleyball, it is imperative to identify the anthropometric constitution, generated by exogenous and endogenous factors. Aim study : The main goal of the research was to determine the factor structure of isolated latent dimensions of the population of female volleyball players of VC \"Jahorina\" Pale, a member of the volleyball Premier League of Bosnia and Herzegovina. Methods: The study involved 18 active players of the women's volleyball club Jahorina (BH=173±8.77cm; BW=66.04±9.09kg; BMI=22.03±2.19kg/m2, age=19.11±2.63 years old) members of the volleyball Premier League of Bosnia and Herzegovina. A set of 15 anthropometric variables was measured in the morphological space with the aim of determining correlations between anthropometric characteristics and identifying the latent morphological structure of volleyball players. Result: Statistical processing of the data was performed by Pearson correlation coefficients and Hoteling principal components analysis (PCA). The results of the correlation analysis showed statistically significant linear correlations between most anthropometric variables (p<0.05; p<0.01; p<0.001). The three-component model, which defined 81.45% of the proportion of the total common variance of the manifest anthropometric variables, was extracted by the method of analysis of the main components, with the Gutman-Kaiser criterion and Varimax rotation. Conclusion : It was structured by hypothetical factors with characteristic roots (Eig.>1), which were interpreted as Factor of volume and longitudinal dimensionality of the skeleton (F1=42.45%; Eig. 6.37>1), Factor of skin folds of the trunk (F2=28. 96; Eig. 4.08>1) and Subcutaneous adipose tissue factor of the lower extremities (F3=10.04; Eig.2.12>1). The correlation of the factors confirmed the inverse relationship of the factors (F1-F2=-0.85; F1-F3=-0.81). It can be concluded that the increased volume of volleyball players is not accompanied by higher values of skin folds, but is a consequence of increased muscle mass.","PeriodicalId":261831,"journal":{"name":"American Journal of Sports Science and Medicine","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134444900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimating Athletes’ Centre of Mass as Presented on Ancient Greek Pottery Depictions","authors":"Andreas G. Bourantanis, Nikitas N. Nomikos, Constantinos C. Trompoukis, Wei W. Wang","doi":"10.12691/ajssm-10-1-3","DOIUrl":"https://doi.org/10.12691/ajssm-10-1-3","url":null,"abstract":"Combat sports pose a discrete thesis in terms of biomechanics among the majority of the sport activities. This research aims to identify and study the position of Centre of Mass (CoM) in ancient Greek Athletes who participated in combat sports, especially in Pankration. This project was carried out by analyzing figures drawn on ancient pottery. The study calculated the CoM using innovative software and programming: OpenPose, Sublime text, Python programming language, and Matplotlib library. According to the results, the study succeeded (for the first time globally) in calculating the CoM of ancient Pankratiasts during the contests.","PeriodicalId":261831,"journal":{"name":"American Journal of Sports Science and Medicine","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131704958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Acute Hormonal Responses to Free Weight and Machine Resistance Exercise","authors":"Andrew C. Fry, Justin X. Nicoll, D. Cabarkapa, Paige N. Stephens","doi":"10.12691/ajssm-10-1-2","DOIUrl":"https://doi.org/10.12691/ajssm-10-1-2","url":null,"abstract":"This study examined acute hormonal responses to multi-joint free weight exercise and single joint machine exercise. Six weight-trained males performed 3 sets of 10 repetitions at 70% of 1RM with one minute rest between each set on either the barbell squat (FW) or three single joint machine weight exercises (MW; i.e., leg curl, leg extension, back extension) using similar primary movers in a randomly-ordered crossover design. Testosterone (T), cortisol (C), growth hormone (GH), and lactate (HLa) were determined from blood samples 15 minutes before (PRE) and 5 minutes after (POST) each exercise session performed at the same time of day. The MW group completed significantly more estimated external work than the FW group (J; MW = 30776±2152, FW = 19728±2399), but the FW protocol resulted in a greater HLa response (mmol . L -1 ; MW, PRE = 1.2±0.1, POST = 6.7±0.7; FW, PRE = 1.5±0.1, POST = 10.5±1.6). Both exercise modalities exhibited similar increases in T (nmol . L -1 ; MW, PRE = 13.4±2.7, POST = 17.6±2.9; FW, PRE = 15.5±2.8, POST = 17.6±3.5) and GH ( µ g . L -1 ; MW, PRE = 1.4±0.3, POST = 6.8±3.3; FW, PRE = 1.1±0.1, POST = 4.3±2.0), despite the lower work performed by the FW protocol. Although C increased for both protocols, the FW session induced a greater C response (nmol . L -1 ; MW, PRE = 463.2±147.8, POST = 448.1±144.1; FW, PRE = 444.4±174.0, POST = 696.9±220.4). While using similar muscle mass, these results suggest that the acute hormonal response is partially dependent on exercise modality. Despite completing less estimated external work, FW exercise protocol yielded similar or greater endocrine responses when compared to MW resistance training modality.","PeriodicalId":261831,"journal":{"name":"American Journal of Sports Science and Medicine","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125159878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of One-side-shoulder Bag Holding with Different Weights on Center of Gravity Shaking during a Standing Posture in Young Women","authors":"Y. Nagasawa, S. Demura, H. Hirai","doi":"10.12691/ajssm-10-1-1","DOIUrl":"https://doi.org/10.12691/ajssm-10-1-1","url":null,"abstract":"Center of gravity shaking (CGS) changes constantly during a standing posture and its variation increases depending on the disturbance stimulus. One-side-shoulder bag (OSB) holding with a heavy weight makes the standing posture unstable because it imposes burden on one side of the shoulder and/or lower back. It is assumed that the effect of OSB on CGS differs by bag weight and the habitual and non-habitual use of one shoulder. This study aimed to examine the effect of different weights and holding shoulders on CGS during OSB in a standing posture in 30 healthy young women aged 21-24 years. The experimental conditions were relative weight loads (0% [non-bag holding], 5%, 10%, and 15% of body mass [BM]) and bag holding shoulder (habitual and non-habitual). The participants maintained a Romberg posture (standing posture with feet closed) with eyes open for 1 minute on the measurement equipment in the above-mentioned eight conditions. The x-axis, y-axis, and total trajectory lengths and outer peripheral area were transmitted to a computer at a sampling rate of 20 Hz. The measurement order was randomized for the different weight loads and holding shoulders. Two measurements were obtained for each condition with a 1-min rest between measurements. The two measurements were then averaged. A two-way analysis of variance (ANOVA) showed that the x-axis, y-axis, and total trajectory lengths were significantly higher for weight loads of 10% BM and above. The outer peripheral area value was significantly lower for the habitual holding shoulder. The 10% and 15% BM weights had significantly higher outer peripheral area values compared with the 0% BM weight, and the 15% BM weight had significantly higher outer peripheral area values compared with the 5% and 10% BM weights. The x-axis, y-axis, and total trajectory lengths and outer peripheral area become greater as bag weight increases over 10% BM. OSB holding leads to a larger outer peripheral area in the non-habitual holding shoulder compared with the habitual holding shoulder in young women.","PeriodicalId":261831,"journal":{"name":"American Journal of Sports Science and Medicine","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126929759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of Training-induced Testosterone and Cortisol Changes on Skeletal Muscle and Performance in Elite Junior Athletes","authors":"J. Bailey, R. Irving, P. Dawson, Dialo-Rudolph Brown, Eon H Campbell","doi":"10.12691/ajssm-9-1-4","DOIUrl":"https://doi.org/10.12691/ajssm-9-1-4","url":null,"abstract":"This study aimed to investigate the influence of testosterone (T) and cortisol (C) on Skeletal Muscle Markers (SMM) at each phase of a track and field macrocycle. On a secondary basis, we also sought to determine whether C or T moderates the relationship between SMM and performance. Twenty-eighth (28) elite junior sprint athletes (15.48 ±1.89 years), and 13 non-athletic (16.15 ±1.51 years), age and gender-matched controls participated in this study. Isometric muscle strength (MS) and muscle thickness (MTH) were considered SMM. Salivary C and T levels, MS and MTH were collected between 2:30 and 3:00 p.m. before training sessions, twice during the preparatory phase [baseline (T1) and midway into the specific preparation period (T2)] and twice in competition phase [midway point of pre-competition (T3) and midway of the major competition period (T4)]. Performance data were collected during the competition phase only. No significant improvements in SMM were observed. T and T/C ratio significantly increased (p<0.05) across the season, while C levels increased relative to baseline only. While T levels did not significantly predict SMM at any phase, C levels significantly explained (p<0.05) a 60% and 74% variance in MTH and performance respectively. However, neither C nor T significantly moderated the relationship between SMM and performance. These findings suggest that raising T levels across a season may be more indicative of a response to training load, rather than a reflection of skeletal muscle adaptation. While training-induced C, which was demonstrated to have a greater influence on SMM is more sensitive to muscle function changes and performance compared to testosterone.","PeriodicalId":261831,"journal":{"name":"American Journal of Sports Science and Medicine","volume":"113 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134090510","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Lower Limbs Exercise with Light and Heavy Loads on the Center of Gravity Sway","authors":"Kenji Takahashi, S. Demura, H. Aoki","doi":"10.12691/AJSSM-9-1-3","DOIUrl":"https://doi.org/10.12691/AJSSM-9-1-3","url":null,"abstract":"Background: Fatigue to the lower limbs due to exercise load affects the center of gravity sway (COGS) during standing, and the greater the load, the greater the COGS. Research Question: Do different exercise loads to the lower limbs have an effect on the COGS and does sitting/resting promote recovery after exercise. Methods: The subjects were 30 healthy young men. The COGS after light and heavy load exercises was compared after a 3-min sitting/resting period before and after the load exercises. For each test, the COGS was measured for 30 s. Bicycle pedaling for 30 s with loads of 1% (light load) and 7.5% (heavy load) of body weight was selected as the load exercise for the lower limbs. The x-axis and y-axis trajectory lengths, total trajectory length, outer peripheral area, and rectangular area were selected as variables affecting the COGS. Results: Repeated measures analysis of variance clarified that of all variables, COGS after heavy load exercises was significantly greater than that after light load exercises and during standing after sitting/resting. However, there was no significant difference in COGS after light load exercise and during standing. Significance: The COGS after heavy load exercise was greater than that after light load exercise. The light load exercise used in this study had no effect on COGS in young men. Even after heavy load exercise, the COGS recovered after a 3-min sitting/resting period.","PeriodicalId":261831,"journal":{"name":"American Journal of Sports Science and Medicine","volume":"87 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124427474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}