The load-velocity profile differs more between men and women than between individuals with different strength levels     

Alejandro Torrejón  Carlos Balsalobre-Fernández  G. Gregory Haff 《Sports biomechanics / International Society of Biomechanics in Sports》2019,18(3):245-255

This study aimed to determine the suitability of the load-velocity relationship to prescribe the relative load (%1RM) in women, as well as to compare the load-velocity profile between sexes and participants with different strength levels. The load-velocity relationship of 14 men (1RM: 1.17 ± 0.19) and 14 women (1RM: 0.66 ± 0.13) were evaluated in the bench press exercise. The main findings revealed that: (I) the load-velocity relationship was always strong and linear (R² range: 0.987–0.993), (II) a steeper load-velocity profile was observed in men compared to women (Effect size [ES]: 1.09), with men showing higher velocities for light loads (ES: ? 0.81 and ? 0.40 for the y-intercept and 30%1RM, respectively), but women reporting higher velocities for the heavy loads (ES: 1.14 and 1.50 at 90%1RM and 100%1RM, respectively); and (III) while the slope of the load-velocity profile was moderately steeper for weak men compared to their strong counterpart (ES: 1.02), small differences were observed between strong and weak women (ES: ? 0.39). While these results support the use of the individual load-velocity relationship to prescribe the %1RM in the bench press exercise for women, they also highlight the large disparities in their load-velocity profile compared to men.  相似文献   

The application of inertial measurement units and functional principal component analysis to evaluate movement in the forward 3½ pike somersault springboard dive     

Cherie Walker  John Warmenhoven  Peter J. Sinclair 《Sports biomechanics / International Society of Biomechanics in Sports》2019,18(2):146-162

Based on technological and analytical advances, the capability to more accurately and finitely examine biomechanical and skill characteristics of movement has improved. The purpose of this study was to use Inertial Measurement Units (IMUs) and Functional Principal Components Analysis (fPCA) to examine the role of movement variability (assessed via angular velocity), on 2 divers (1 international level; 1 national) performing the forward 3½ pike somersault dive. Analysis of angular velocity curves during ive-flight identified 5 fPCs, accounting for 96.5% of movement variability. The national diver’s scatter plots and standard deviation of fPC scores illustrated larger magnitudes of angular velocity variability across dive flight. For fPC1 and fPC3, magnitudes of SD variability were 282.6 and 201.5, respectively. The international diver illustrated more consistent angular velocity profiles, with clustering of fPCs scores (e.g., fPC1 & 3 = SD’s of 75.2 & 68.0). To account for lower variability in the international diver, the ability to better coordinate movement sequences and functionally utilise feedback in response to initiation of the somersault position is highlighted. Overall, findings highlight how both IMUs and fPCA can more holistically and finitely examine the biomechanical and skill characteristics of movement sequences with the capability to inform athlete development.  相似文献   

Twenty-four-hour movement behaviours and fundamental movement skills in preschool children: A compositional and isotemporal substitution analysis     

Jéssica Gomes Mota  Cain Craig Truman Clark  Luís Lemos  Cézane Priscilla Reuter  Jorge Augusto Pinto Silva Mota 《Journal of sports sciences》2020,38(18):2071-2079

ABSTRACT

Studies that have analysed the association between the different movement behaviours and fundamental movement skills (FMS) have considered it in an independent manner, disregarding the compositional nature of 24-h movement behaviours (24-h MB). The aim of this study was to investigate the relationship between the 24-h MB and FMS in preschoolers using a compositional data analysis . Two hundred and four preschoolers (4.5 ± 0.8 years old; 101 boys) provided objectively assessed physical activity (PA) and sedentary behaviour (SB) data (Actigraph wGT3X), and FMS (TGMD-2). Sleep duration (SD) was reported by parents. Association of daily composition of movement behaviours with FMS was explored using compositional analysis and isotemporal substitution (R Core Team, 3.6.1). When considered as a 24-h MB composition (PA, SB and SD), adjusted for age, BMI and sex, the composition predicted locomotor (r² = 0.31), object control (r² = 0.19), and total motor score (r² = 0.35), respectively (all P < 0.001). Reallocation of time from light to moderate-to-vigorous PA was associated with greatest positive changes in total motor score. Achieving adequate balance between movement behaviours over the 24-h period, and its relationship with locomotor and object control skills should be considered and further investigated in early childhood.  相似文献   

试析延安整风运动与建国初期的整风运动之异同     

尹凌霞 《邵阳学院学报(社会科学版)》2011,10(2):29-31

延安整风运动和建国初期的整风运动,在中共党史上都占有非常重要的地位。文章拟从整风发生在关键时刻、整风的方法、党的领导与当时的中心任务三个方面来分析两次整风的相似之处;从发生的背景、内容、准备和进行的时间以及存在和遗留的问题等几个方面来阐述他们的相异之处,以期对党史研究能提供有益借鉴。  相似文献   

美国对加拿大联邦议会制度的影响     

李节传 《天津师范大学学报(社会科学版)》2003,23(2):33-37

加拿大联邦议会制在1867年建立时，实行的是在联邦制形式下尽可能强大集中的联合，原设想应能以此避免美国联邦制的偏失。在美国，各州拥有立法权；在加拿大，立法权由联邦议会掌握，省的责任与职能相对较小。然而，正如美国政治演变所显示，联邦制的联合是一种分裂的议会形式；因而，加拿大自治领自建立后已开始分裂。  相似文献   

《新青年》在妇女解放中的作用     

张爱青 《山西师大学报(社会科学版)》2002,29(3):102-105

《新青年》是中国近代史上颇具影响的刊物之一，它在提倡民主与科学的同时，猛烈评击建设礼教，否定妇子片面贞操观，积极号召妇女冲破封建罗网，恢复独立人格，强烈呼呈妇女冲泱礼教大防，参与社会政治，尤其在十月革命之后，它以马克思主义理论为武器，探讨妇女解放道路，成为当时倡导妇女解放的主要阵地，对推动近现代妇女解放运动起到了积极的促进作用。  相似文献   

教育科学化的早期探索——欧美教育科学研究运动简析     

郭法奇 《教育文化论坛》2021,(1):1-8

19世纪后期至20世纪初期,欧美出现的教育科学研究运动是教育研究领域一次具有深远意义的运动它的出现与这个时期欧美社会新的发展和教育的深刻变革,以及人们对科学、科学与教育关系的认识有密切的联系。根据欧美教育科学研究运动中一些突出的事件加以划分,其发展可以分为四个阶段,且每个阶段都有其显著的特点。19世纪末至20世纪初期,欧美出现的教育科学研究运动是现代科学研究思想和方法在教育研究领域里的初次运用和实践,其所关注的领域和所争论的问题值得今天反思与借鉴。  相似文献   

"云娜"台风暴雨的Q矢量与螺旋度诊断分析   总被引：5，自引：0，他引：5  

朱健  沈晓玲 《科技通报》2007,23(1):22-27

利用非地转ω方程说明了Q矢量散度的物理意义,并通过计算台风“云娜”影响过程中的Q矢量散度和高低空螺旋度,分析了这两个物理量的演变特征及其与台风、台风暴雨的关系,指出低层等压面上Q矢量散度场及相对螺旋度对台风暴雨预报具有较好的参考价值。  相似文献   

问题解决的信息机制     

刘春年  娄策群 《情报科学》2004,22(7):878-880

阐述了信息科学中的一些基本问题，并利用信息科学的观点对问题解决理论进行了分析和总结，从而对问题解决概念、影响因子与问题解决过程中的信息活动模式和信息机制有了新的比较深入的认识。所得结论对问题解决方法研究和表象与环境相互作用的系统设计具有一定的参考价值。  相似文献   

陈式太极拳竞赛套路演练动作节奏变化规律探析     

孙春艳  郭颖  李文军 《沧州师专学报》2011,(4):95-99

通过文献资料法、调查访问法、实验法、录像观察法和逻辑分析法对陈式太极拳竞赛套路的演练节奏进行分析研究。研究认为,节奏鲜明体现了陈式太极拳独特的韵味。陈式太极拳竞赛套路从头到尾有快有慢、有高潮有舒缓、波浪式前进。套路中的每个动作组合、每个段落都是由刚柔相济的动作相互衬托、鲜明对比构成的。在研究动作的基础上,对如何准确掌握陈式太极拳竞赛套路演练过程的动作节奏变化规律提出几点建议。  相似文献