Validity and reliability of a linear positional transducer across commonly practised resistance training exercises     

Harry F. Dorrell  Joseph M. Moore  Mark F. Smith  Thomas I. Gee 《Journal of sports sciences》2019,37(1):67-73

This study investigated the validity and reliability of the GymAware PowerTool (GPT). Thirteen resistance trained participants completed three visits, consisting of three repetitions of free-weight back squat, bench press, deadlift (80% one repetition maximum), and countermovement jump. Bar displacement, peak and mean velocity, peak and mean force, and jump height were calculated using the GPT, a three-dimensional motion capture system (Motion Analysis Corporation; 150 Hz), and a force plate (Kistler; 1500 Hz). Least products regression were used to compare agreeability between devices. A within-trial one-way ANOVA, typical error (TE; %), and smallest worthwhile change (SWC) were used to assess reliability. Regression analysis resulted in R² values of >0.85 for all variables excluding deadlift mean velocity (R² = 0.54–0.69). Significant differences were observed between visits 3-2 for bench press bar displacement (0.395 ± 0.055 m; 0.383 ± 0.053 m), and deadlift bar displacement (0.557 ± 0.034 m; 0.568 ± 0.034 m). No other significant differences were found. Low to moderate TE (0.6–8.8%) were found for all variables, with SWC ranging 1.7–7.4%. The data provides evidence that the GPT can be used to measure kinetic and kinematic outputs, however, care should be taken when monitoring deadlift performance.  相似文献   

Reference power values for the jump squat exercise in elite athletes: A multicenter study     

Pedro L. Valenzuela  Michael McGuigan  Guillermo Sánchez-Martínez  Elaia Torrontegi  Javier Vázquez-Carrión  Zigor Montalvo 《Journal of sports sciences》2020,38(19):2273-2278

ABSTRACT

The present study aimed to provide reference values for lower-limb muscle power assessed during the incremental jump squat (JS) test in elite athletes (i.e., professional athletes competing at international level). We pooled data from all JS tests performed by elite athletes of different sports in two high-performance centres between 2015 and 2019, and computed reference values (i.e., terciles) for mean power (MP), mean propulsive power (MPP), and peak power (PP). Reference values were obtained from 684 elite athletes (458 male and 226 female) of 16 different sports (boxing, judo, karate, fencing, taekwondo, wrestling, basketball, soccer, futsal, handball, rugby union, badminton, tennis, long distance running, triathlon, and sprinting). Significant differences (p < 0.001) were found between male and female athletes for MP (7.47 ± 1.93 and 6.15 ± 1.68 W·Kg^?1, respectively), MPP (10.50 ± 2.75 and 8.63 ± 2.43 W·Kg^?1), and PP (23.64 ± 6.12 and 19.35 ± 5.49 W·Kg^?1). However, the velocity at which these power measures was attained seemed to be independent of sex (~0.95, 1.00 and 2.00 m·s^?1 for mean, mean propulsive, and peak velocity, respectively) and homogeneous across different sport disciplines (coefficient of variation <10%). These data can be used to classify athletes’ power capabilities, and the optimum velocity ranges provided here could be useful for training purposes.  相似文献   

体育强国视域下我国网球的发展趋势     

黄中俊 《体育科技文献通报》2020,(6):74-75,82

近几年来,我国网球运动蓬勃发展,前程似锦,但是世界级网球高手随处闪现,在技战术水平、心理素质等都优于同龄中国选手。不难发现,我国距离体育强调还有很长一段距离,只有大家齐心协力,共同努力,明确网球发展动向,才能实现体育大国向体育强国的跨越。因此,本文首先介绍新时期体育强国的要求,然后分析我国网球与世界网球强国的差距,最后研究体育强国视域下我国网球发展趋势。  相似文献   

新时代我国体育消费力提升研究     

孙威  王晓辉 《沈阳体育学院学报》2020,(3):49-55

当前我国体育消费力较弱,亟需通过研究提升体育消费力。运用文献资料、逻辑分析等方法,依据马克思消费力理论提出并解析了体育消费力的4要素及其现实情况:体育供给不到位导致消费品难以满足需求、居民收入不平衡限制消费者的支付能力、体育环境不规范阻滞良好消费氛围的形成、体育消费者不成熟拉低消费力的整体水平。体育消费力提升路径:以供给侧结构性改革为主线有效优化体育供给力,以拓宽人民增收渠道为手段动态平衡居民可支配收入,以完善市场化引导监督机制为动力合理规范体育社会环境,以强化消费者要素整合能力为抓手全面提升体育消费者成熟度。  相似文献   

Mapping continuity and change in the intellectual structure of the knowledge base on problem-based learning, 1974–2019: A systematic review     

Philip Hallinger 《British Educational Research Journal》2020,46(6):1423-1444

Problem-based learning (PBL) emerged during the 1970s in response to demands for active learning methods capable of developing transferable knowledge and skills in the training of doctors. Over succeeding decades, PBL was gradually adopted in other fields of education. This systematic review aimed to identify key streams of theory and empirical research that have emerged over time in PBL research and practice. The review sourced 12,036 Scopus-indexed documents published between 1974 and 2019. Science mapping was used to reveal the ‘intellectual structure’ or key research themes that have evolved in this literature over the past 45 years. The science mapping tool used in this review was author co-citation analysis conducted in VOSviewer software. Author co-citation analysis identified three schools of thought that together describe the intellectual structure of the PBL knowledge base: Design of PBL Curriculum and Instruction; PBL Effectiveness; Theory and Practice in Active Learning. In addition to portraying the intellectual structure of the literature as a whole, the review also conducted longitudinal analyses aimed at highlighting structural changes in this field over time. These analyses found that although the size and impact of schools of thought associated with Design of PBL Curriculum and Instruction and PBL Effectiveness increased over time, they remained stable in terms of theoretical foci. However, the Active Learning school evolved from a small school of authors associated with Cognitive Learning Theories prior to 2000 into the largest school of thought during the most recent decades. These findings both reaffirm the theoretical underpinnings of the PBL knowledge base and highlight its increasing integration with other forms of active learning.  相似文献   

Physiological responses in different intensities of resistance exercise – Critical load and the effects of aging process     

Vivian Maria Arakelian  Cássia da Luz Goulart  Renata Gonçalves Mendes  Nuno Manoel de Sousa  Renata Trimer  Solange Guizilini 《Journal of sports sciences》2019,37(12):1420-1428

Aim was to identify critical load (CL) in young and elderly apparently healthy male cohorts. To contrast the metabolic, cardiovascular and perceptual responses on CL according to age. We evaluated 12 young (23 ± 3 years) and 10 elderly (70 ± 2 years) apparently healthy active males, who underwent: (1) 1 repetition maximum (1RM) test on a 45° Leg Press; (2) on different days, three high-intensity resistance exercise constant load tests (60%, 75% and 90% 1RM) until fatigue (Tlim). Absolute values of both the CL asymptote and curvature constant (kg) were significantly lower in elderly subjects (P < 0.05). In contrast, elderly subjects demonstrated a significantly higher number of repetitions at CL when compared with young subjects (P < 0.05). As expected, oxygen uptake (VO₂) and heart rate (HR) during maximal aerobic exercise testing were significantly reduced in older subjects. However, percent-predicted aerobic capacity were higher in older subjects (P < 0.05). In addition, blood lactate ([La^?]) corrected to Tlim and rating of perceived exertion values were greater in younger subjects at all intensities (P < 0.05). These findings, despite reduced force production in older subjects, endurance-related parameters are well preserved according to age-adjusted percent-predicted values in apparently healthy males.  相似文献   

古代“淮南”政区沿革及其演化规律     

于朕朕 《兰台世界》2020,(4):129-133

汉初,高祖先后封英布、刘长为淮南王,国除后为九江郡。曹魏时又有淮南王之封,西晋时为淮南郡。东晋南朝由于侨置郡县,淮南郡出现名实不符的现象。十六国北朝也有淮南郡的设置,且名实相符。隋唐及以后,淮南郡改为寿州。唐时淮南道为十道之一,唐末演变成淮南节度使。宋时,淮南或为一路或为淮南东西两路。此后元明清至民国,“淮南”二字不再作为正式政区名称。从“淮南”政区的演变中,我们可以发现二级制与三级制的循环、分封到郡县的逐渐确立、同级政区幅员总是由大到小、政区设置多受前朝影响等中国历代行政区划演变的一般规律。  相似文献   

体育强国建设下幼儿家庭体育的现象学研究     

白翠瑾  李哲  杨光 《沈阳体育学院学报》2020,(2):34-40

2019年是中国体育划时代的一年,以《体育强国建设纲要》的颁布为起点开启了体育事业的全新征程。幼儿家庭体育是学前教育的薄弱环节,父母的体育引导是家庭体育的重中之重。采用现象学方法,以幼儿父母访谈为抓手诠释幼儿家庭体育现象。结果认为:父母观念下幼儿家庭体育的掣肘包括主观因素的理念束缚、安全焦虑、指导孱弱、精力局限,客观因素的经济无力、规划无序、保障无依。针对存在障碍提出化解路径:通过革新理念调解传统意识的偏颇,通过制定指南消解育教于体的困惑,通过家园共育缓解精力、经济的压力,通过社会支持纾解供需之间的失衡。  相似文献   

协同学视域下体育教学协同发展动力研究     

苏尔健 《体育科技文献通报》2020,(6):156-158

运用文献资料法,并以协同学理论为研究工具,研究分析了现代体育教学的发展,同时找出现代体育教学发展的促进因子。研究认为:在子系统之间,体育教学发展的内在动力是“协同”和“竞争”,体育教学组织系统与外界因素的“协同”与“竞争”是其发展的外在推动力,序参量的“协同”与“竞争”是其发展的核心动力。  相似文献   

耗散结构理论在校园足球训练中的初探     

金旭 《体育科技文献通报》2020,(6):65-66,79

近年来校园足球得到高度重视,但是各个地方的中小学足球训练方法还是比较陈旧,教师没有开放自己的思想,导致实施的结果与成绩不理想,因此本文尝试将耗散结构理论与混沌融入校园足球训练中,尝试探讨耗散结构理论在校园足球训练中的应用。使我国足球训练达到一定的水平及高度,首先要做的是学校体育管理者、足球教练、学生以及学生家长们在足球训练发展的各方面保持思想的开放性、远离平衡态,从而推动我国校园足球训练的健康全面发展,形成一套训练方法理念以及训练体系。  相似文献