举重抓举和下蹲翻运动学比较与用力特征分析

本研究的目的,是运用生物力学的研究方法,对我国高水平的女子举重运动员的抓举和下蹲翻进行运动学比较分析,并对其力量的特点进行比较分析;此外,运用逆向动力学对两种技术动作的主要关节的净力矩进行了分析,为更深刻地理解抓举和下蹲翻动作的差异和力量特点提供参考的依据。本文研究对象是:参加2003年4月在河南平顶山举行的全国女子举重锦标赛的10名运动员。结论:本研究运用生物力学的分析方法,对举重的抓举和下蹲翻技术动作,在动作的结构、力量的特点以及关节受力等方面进行了较为全面的比较分析,对于更深一步地了解其动作的结构和力量的特…     

奥运冠军石智勇抓举技术运动学分析

运用三维运动学的研究方法,对参加2005年全国第十届体育运动会举重比赛的运动员石智勇的抓举技术进行运动学分析。结果表明,提铃过程中人杠重心间距控制合理,杠铃平均加速度超过2 m/s2,体现了优异的爆发力和出色的提铃技术;引膝阶段的技术与常规引膝技术已有了很大的改变,该阶段用时很短,膝关节角度也几乎没产生变化,通过对膝关节的制动充分发挥了腰背部肌肉力量,使抓举时杠铃最高加速度的值出现在引膝阶段而非发力阶段,这是最体现石智勇抓举技术特点的地方;抓举发力阶段,身体用力协调,各关节角度的把握也恰到好处;抓举下蹲支撑阶段技术动作堪称完美,人杠重心间距控制合理,杠铃回落距离仅为13.6 cm,人体重心向下的平均加速度为11.2 m/s2,两项均属于世界顶级选手的技术指标;在起立阶很好地利用了杠铃的弹性势能,与杠铃同步起立,同时人杠重心间距仅为0.002 m,确保了起立的稳定性。     

山东省优秀男子举重运动员抓举技术动作生物力学分析

根据定性与定量相结合的原则,采用摄像解析及三维测力相结合的方法,对山东省男子举重队6名运动员的抓举动作进行诊断和评价,为其改进技术动作,提高运动成绩提供参考依据.研究结果表明,抓举过程中杠铃中心点运动轨迹应尽可能成垂直直线向上,S型弧度要小,发力后杠铃应达到一定最大速度,部分优秀运动员下蹲时加速度大于自由落体加速度,杠铃上抛中心点与身高的比值应控制在70%左右.抓举过程中人体膝关节角度曲线成双峰,而髋关节角度曲线为单峰,髋关节不可过早打开,躯干也不可过早用力.抓举整个过程环环相扣,每个阶段的发挥对下一阶段均有重要影响,对抓举的技术分析应采用系统的思考方法.     

优秀运动员谌利军与冯吕栋抓举技术对比研究

运用三维运动学研究方法,对参加2019年亚洲举重锦标赛暨东京奥运会资格赛的我国男子举重67kg公斤级优秀运动员谌利军与冯吕栋抓举技术进行对比分析。研究结果认为:提铃准备阶段,冯吕栋身体姿势更符合抓举中“近”的技术要求;总体上,冯吕栋伸膝提铃和引膝提铃阶段技术动作优于谌利军,谌利军发力和惯性上升及接铃阶段技术动作优于冯吕栋。谌利军抓举过程中主要存在伸膝提铃阶段髋关节打开过早,引膝提铃阶段膝关节回屈角度小以及整个抓举过程中杠铃重心左右偏移量过大的问题;冯吕栋主要存在发力和惯性上升阶段“两心”前后距离过大,杠铃相对于运动员水平运动幅度大,垂直运动幅度小以及接铃过程中杠铃下落距离长,下降速度过快的问题。建议谌利军加强膝关节主要屈伸肌群的力量训练以及进行身体左右侧力量平衡的评估;冯吕栋应掌握在发力和惯性上升阶段正确的用力方向,并改善接铃节奏。     

基于人/杠合重心与支撑面中心关系对抓举失败原因的研究

研究运用三维运动学方法,获取评价抓举技术动作稳定性的量化指标,并对廖辉、石智勇等5名运动员8次成功试举与7次失败试举中每个特征时刻该指标进行对比分析,旨在从动作稳定性的角度分析抓举失败的原因。研究认为人/杠合重心与人体支撑面中心在前后方向的距离(两心差)是评价运动员抓举技术动作各阶段稳定性的重要指标,两心差越小,技术动作稳定性越强。抓举过程中运动员的两心差数值曲线呈现出双波峰双波谷的特点,较为合理的两心差变化趋势应该是:两心差于发力阶段初达到第一个波谷,惯性上升阶段初达到第一个波峰,于下蹲支撑初达到第二个波谷,杠铃速度最大时刻达到第二个波峰。大多数抓举试举失败都出现在接铃完成阶段,而下蹲支撑阶段两心差过大是导致运动员在接铃完成阶段无法对杠铃形成有效制动的重要原因。研究中成功试举在接铃完成阶段末两心差几乎为零;接铃完成末两心差过大,将导致运动员在上举时失去平衡。     

位移速度传感器在举重提拉发力过程实时分析中的应用研究

通过位移和速度传感器对举重专项练习的实时测试,获得举重运动员发力上拉杠铃的力学数据。结果显示运动员提拉杠铃的最大高度、最大速度和提拉重量之间存在显著性负相关;最大速度出现的相对高度因人而异,彼此显著差异;最大力、最大功率与提拉重量没有明显相关关系。通过次极限重量的回归估计,可得到每个运动员的极限提拉重量。分析表明此极限重量与每个运动员的抓举挺举成绩显著相关,从而较细致的量化运动员的提拉能力;在次重量练习过程评估运动员的能力增长状况;有效地监控训练效果,客观地评价运动能力。     

高水平与一般水平举重运动员抓举技术的生物力学

本文比较了10名世界水平的举重运动员与26名一般水平的大学生运动员在完成抓举的提铃动作——从杠铃离地到把杠铃举过头顶,身体成下蹲支撑时的技术。采用影片分析的方法测量关节角度、身体重心位置和杠铃的位置。结果表明,世界水平的运动员比一般水平的运动员举起杠铃的高度都相对较低,在上举的一定时期,髋、膝关节屈曲较深,小腿与地面的夹角也较小,下蹲阶段身体下降较快。     

对陕西省女子举重运动员朱丁梅抓举技术的运动学分析

方法:运用高速摄相和三维运动解析的方法对运动员的抓举技术进行研究.目的:通过对运动员朱丁梅抓举技术的分析找出运动员技术上存在的不足并进行改进,帮助运动员取得更好的成绩.结果表明:(1)运动员膝关节角、髋关节角比较合理,在发力阶段伸髋不充分.(2)杠铃的运动轨迹偏向后方,没有呈现近似s型,运动员发力时有明显的后跳动作.(3)各阶段时间比和杠铃上升高度比整体较合理,精细化程度不够.结论:(1)发力阶段伸髋不充分影响了运动员的成绩.(2)两心向运动员后上方偏移,抓举技术动作不符合"近"的原则.(3)运动员在抓举90kg时过早发力,当杠铃高度达到最高点时杠铃在支撑点后方不利于支撑,导致后掉失败.(4)抓举的总体节奏较好但是精细化程度还不够.(5)对运动员的后跳动作不予以纠正.     

我国优秀女子举重运动员主要专项辅助动作成绩与竞赛动作成绩相关分析

采用文献资料、专家访谈、问卷调查、数理统计等研究方法,对我国优秀女子举重运动员主要专项辅助动作成绩与竞赛动作成绩进行相关研究。结果显示:主要专项辅助动作成绩与竞赛动作成绩具高度显著性相关;高抓、高翻借力推、宽硬拉成绩与抓举成绩,下蹲翻半挺成绩与挺举成绩直接相关;高抓、高翻借力推、下蹲翻半挺成绩共同作用影响抓举成绩;下蹲翻半挺、前深蹲成绩共同作用影响挺举成绩;主要专项辅助动作成绩受爆发力和绝对力量的影响。     

优秀女子举重运动员抓举与借力推的相关探讨

在女子举重训练中，抓举与高翻成绩呈比例关系，高翻与下蹲翻成绩呈比例关系，高抓与下蹲抓成绩呈比例关系。实践中还发现，抓举与借力推成绩有着非常近似的现象，关于两者的论述目前未见报道。本文试图通过对部分优秀女子举重运动员借力推在抓举中的运用进行实验对照，同时对调查数据进行相关分析，探讨两者的相互关系，为女子举重训练提供参考依据。     

优秀男子举重运动员专项成绩与下肢等速肌力相关回归分析

采用德国IsoMed 2000等速肌力测试仪，对17名健将（健将组）和18名一级（一级组）男子举重运动员进行双侧髋、膝和踝关节60°/s、120°/s、180°/s和240°/s向心、离心（每种角速度5次）测试。探讨优秀男子举重运动员下肢关节不同角速度等速肌力的特征，比较健将与一级组间差异，对健将组下肢关节相对峰力矩与相对专项成绩进行Pearson相关分析，并建立抓、挺举与峰力矩多元线性回归方程。结果显示，优秀男子举重运动员的髋关节相对伸爆发力与相对抓举呈高度显著正相关，髋关节中速（120°/s）、膝踝关节相对伸爆发力与相对抓举呈中度显著正相关，而踝关节相对屈绝对力呈中度显著负相关；髋关节相对伸爆发力与相对挺举呈高度显著正相关，左膝（挺举弓步腿）相对中速（120°/s）、爆发力和踝关节相对爆发力与相对挺举呈中度显著正相关。     

女子举重运动员抓挺举发力阶段等动肌力的特征

采用高速摄影与等动测试相结合的研究方法,对女子举重运动员抓挺举时的等动肌力特征进行探讨。结果显示,抓举发力阶段,提肘动作发生在伸髋结束时,不同关节等动肌力的比值反映了举重发力动作的先后顺序;抓举与挺举上挺发力阶段的最大相关速度与上肢等动测试的峰力矩,平均功率相关指标有显著性相关,而最大速度与等动测试的峰力矩、平均功率指标无相关性。     

全国举重冠军伍超抓举154kg的技术特征分析

通过SIMI°Motion三维录像分析系统,对2011年全国举重冠军赛冠军伍超的抓举技术动作进行运动学分析,揭示其抓举154 kg的技术特征。结果显示:伍超的身体重心和杠铃重心距离较近,并在整个提铃过程中杠铃重心的垂直速度呈上升趋势;膝关节角、躯干角、髋关节角、杠铃中心点垂直速度随时间变化曲线符合抓举的技术特点;从整体上看,伍超的技术较为合理,且有较大的提升空间。     

Distribution of lower extremity work during clean variations performed with different effort

The purpose of this research was to investigate how lower extremity work was distributed during the pull of cleans performed lifting the barbell to the minimum height required to receive it in a full squat (minimal height clean); or with maximum effort to elevate the barbell as high as possible and receiving it in either a full (maximal effort clean) or partial (power clean) squat. Eight weightlifters screened for proficient technique performed these clean variations at 80% of one repetition maximum. Work performed on the barbell and by the lower extremity net joint moments (NJM) was computed from marker trajectories and ground reaction forces. Total barbell work, lower extremity NJM work, knee extensor work, and knee joint excursion during the second pull was lower in the minimal height clean than the maximal effort and power cleans (P < 0.05). This research demonstrates that more knee extensor work is performed in the second pull of maximal effort and power cleans compared to the minimal height clean. The larger knee extensor work performed is due to larger knee joint excursion during the second pull of the maximal effort and power cleans, but not larger knee extensor NJM.     

Biomechanical analysis of the snatch technique in junior elite female weightlifters

The strength and technical competence of junior female lifters play a decisive role not only for their current but also adulthood performance. The objective of this study was to investigate the three-dimensional kinematics of the snatch technique in junior female weightlifters. Ten elite junior female weightlifters participated in the study. Two cameras operating at 50 fields per second were used to record the lifts. The heaviest successful lifts were selected for the kinematic analysis. The kinematical data were obtained using a motion analysis system. The duration of the first pull was significantly longer than that of the other phases (P < 0.05). Maximum extension angle and velocity of the lower limb joints were significantly greater in the second pull (P < 0.05). The greatest extension angle was found in the knee joint during the first pull, while the greatest extension angle was observed in the hip joint during the second pull (P < 0.05). Maximum extension velocity of the knee and hip joints was significantly greater than that of the ankle in both phases (P < 0.05). In addition, the vertical velocity of the barbell and the absolute and relative power outputs was significantly higher in the second pull than in the first pull (P < 0.05). In the snatch lifting of junior female weightlifters, the angular kinematics of lower limb joints, the linear kinematics and trajectory of the barbell and other energy characteristics are similar to and consistent with the values reported in literature for adult female weightlifters.     

The influence of deformation on barbell mechanics during the clean pull

For simplicity of biomechanical analyses, the weightlifting barbell is typically modelled as a rigid, nondeformable object. Most coaches and weightlifters, however, are aware of the elastic nature of the barbell, and its influence on the successful completion of lifting attempts. Variables such as velocity, work performed, and power output are indicators of the quality of performance during the snatch, clean, and related weightlifting pulling movements. The aim of this study was to establish whether differences exist in determining these biomechanical parameters when the centre of the barbell is analysed compared with each end of the barbell. Nine men performed three maximal-effort repetitions in the clean pull exercise at 85% of their self-reported single repetition maximum (1-RM) clean (90-155 kg) using a barbell instrumented for mechanical analysis. Results indicated that peak barbell speed was 5-30% (P < 0.05) lower for the centre of the barbell than the ends. Although differences (P < 0.05) in kinetic and potential energy were found between the centre and ends of the bar, differences between total work performed were small (< 6%; P < 0.05) and no differences were observed for average power (P > 0.05). Although approximately the same work and power occur for the centre and ends of the barbell, they manifest as different kinematics as a result of the elastic nature of the equipment. The elastic characteristics should be considered when selecting instrumentation and variables for research involving barbells. Coaches should be aware of the elasticity of barbells, including selecting appropriate viewing angles as well as understanding how deformation may affect the ends of the barbell relative to the centre.     

Patterns of barbell acceleration during the snatch in weightlifting competition

The purpose of this study was to determine the association between weightlifting performance and vertical barbell acceleration patterns. Barbell kinematic time-series data were tracked from 18 snatches from six weightlifters during a regional weightlifting competition. These data were used to calculate vertical barbell accelerations. Time-series data were normalised to 100% of lift phase, defined as the time interval between barbell lift-off and maximum height of the barbell during each snatch lift. The time-series data were then entered into a pattern recognition algorithm that extracted principal patterns and calculated principal pattern scores. Body mass-normalised lift weight, which was used to quantify weightlifting performance, was significantly correlated (r = 0.673; P = 0.033) with a pattern that captured a difference in peak vertical barbell acceleration between the transition and the second pull phase. This correlation indicated that barbell acceleration profiles of higher weight snatch lifts were characterised by smaller decreases in acceleration during the second knee bend and smaller peak acceleration during the second pull phase. Weightlifting coaches and sports scientist should monitor and track vertical acceleration of the barbell, with focus on acceleration profiles that limit (1) deceleration during the transition phase between the first and second pull and (2) peak acceleration during the second pull phase of the snatch.