我国高水平女子链球运动员张文秀和王峥投掷技术特征研究

通过专家访谈、运动学测试、动力学测试和肌电测试等方法对我国高水平女子链球运动员张文秀和王峥投掷技术进行研究,得出以下结论:链球的旋转助跑技术表现出"转动+平动"的技术特征,摆动腿SEMG具有积极主动着地运动特征;中国高水平女子链球运动员转换技术具有"低、平、快"技术特征,最后用力阶段具有右腿"快着地"技术特征.     

不同踢球方式摆动腿的运动学与肌电信号特征研究

为研究脚背内侧踢球、脚背正面踢球、脚内侧踢球以及脚背外侧踢球4种基本踢球方式摆动腿的运动学和肌肉力学特征,获取人体运动内外信息,运用三维运动学分析与表面肌电信号特征分析的方法对其研究发现,4种基本踢球方式摆动腿的摆动时间、摆动幅度以及摆动速度均表现出不同特点;后摆阶段摆动腿肌群的兴奋程度表现出了较好的一致性,而前摆阶段摆动腿肌群的兴奋程度表现出了较大差异性;此外,股二头肌在前摆阶段对关节的控制程度与踢球精度间存在一定相关性。     

不同级别优秀散打运动员鞭腿技术动作特征及其对击打速度的影响

为探求优秀散打运动员的体重差异与鞭腿技术动作特征是否对击打速度产生影响。方法：运用VICON Nexus 3D运动捕捉系统,对小、中、大三个级别15名运动员运用鞭腿技术动作快速击打目标物时的运动轨迹进行采集。依据鞭打动作特点和下肢关节运动特征,将技术动作划分为四个时刻、三个时段,并对四个时刻下肢关节的角度以及三个时段的动作位移、时间、速度、角速度等运用VICON Polygon分析软件进行计算。结果表明：启动时段（P1）小级别运动员的躯干和支撑腿各关节运动幅度呈"上大下小"状态,大级别运动员呈"上小下大"状态;三个级别运动员作用腿下肢关节的运动方向相同,运动幅度却出现差异,小级别运动员启动时段的动作速度相对较快。击打时段（P2）三个级别运动员支撑腿的髋、踝关节回旋运动方向出现差异;作用腿下肢关节运动方向相同,中级别运动员膝关节屈曲角度相对较大、转动半径相对较小,击打时段的动作速度也相对较快。回收阶段（P3）三个级别运动员支撑腿髋关节屈伸、回旋运动方向出现差异;作用腿下肢关节运动方向相同,小级别运动员作用腿下肢关节转动半径相对较小,回收时段的动作速度也相对较快。不同级别运动员鞭腿技术动作特征对击打速度存在显著性差异,相同级别散打运动员减轻体重、改善下肢关节的运动方向和运动幅度,才是提高击打速度的重要途径。     

我国优秀男子跳高运动员起跳阶段摆动腿技术的运动学研究

背越式跳高起跳技术主要由起跳腿的蹬伸技术与摆动腿的摆动技术所组成。目前,大多数人们集中于跳高起跳的"蹬伸"技术研究,对起跳阶段的"摆动"技术研究相对较少。文章运用现场技术录像和运动图像解析的方法,对我国优秀男子跳高运动员在起跳阶段摆动技术进行解析研究,结果表明:我国优秀男子跳高运动员起跳前摆动腿最大缓冲幅度比较大;在起跳阶段摆动腿蹬离瞬间,摆动腿膝关节角度变化较小。背越式跳高起跳过程中的摆动腿缓冲阶段,身体重心的高度、摆动腿膝角的变化情况与助跑水平速度的损失有显著性相关。助跑最后一步摆动腿的伸膝角度、伸膝速度与起跳腿着地时摆动腿的摆动速度、摆动腿离地后的最大摆动速度都有高度的相关性。     

跳高起跳准备技术的运动学分析

对索托马约尔等4名世界优秀跳高运动员的比赛技术录像和技术图片进行统计分析后发现,背越式跳高的整个助跑过程所表现出的技术动作都是为完成良好的起跳做准备,所有的技术环节都直接影响运动员起跳效果。结合运动训练实践从运动员助跑节奏、倒三步起跳腿支撑、倒二步摆动腿支撑以及最后一步的起跳支撑4个方面对背越式跳高运动的起跳准备技术特点进行了运动学分析,总结出运动员采用步频型和步幅型、倾斜支撑型和屈腿支撑型等不同准备技术的特点。     

男子跳高一二级运动员髋关节肌力特征对比研究

采用等速测力实验等研究方法，对男子跳高一二级运动员髋关节肌力进行测试分析。发现两者表现出以下肌力平衡特征：一级运动员髋关节的肌力特征与跳高起跳技术用力特点相一致，即摆动腿髋关节屈肌力显著大于起跳腿，屈肌缺失值和伸肌缺失值较大；摆动腿髋关节屈伸比大、起跳腿小。而二级运动员髋关节肌力矩未表现出此特征。     

从运动力学角度对散打侧踹腿技术分析与研究

运用文献资料、录像观察、运动力学实验及数理统计等方法,对徐州市10名专业散打运动员侧踹腿技术进行了运动力学分析,找出侧踹腿技术的差异性和共同特征,总结出高质量完成这一动作的运动规律和技术特点,旨在为散打教学和训练提供定量的数据和理论参考。     

武术散打侧踹腿技术特点及训练与应用探讨

侧踹腿技术在武术竞技散打运动中,以速度快、力量大、不易防守为特点,它高可击头、中可击胸、底可击腿,以灵活多变、命中率高,进可攻击、退可阻击等技术风格在散打比赛中是取胜的优势技法.文章通过对多种腿法的对比分析,指出侧踹腿的技术特点与其利弊关系,应用运动解剖学、生理学、力学等分析,以探讨侧踹腿技术的合理性与实用价值,为竞技武术散打训练的指导提供参考.     

浅析儿童阶段游泳基础训练

<正>儿童的早期运动训练是基础的训练阶段,作为业余少体校主要的训练任务,就是打好各种基础,游泳项目也是如此。如基础阶段的四种泳式的"打腿"、身体姿势、手及手腿配合的技术,还有身体各方面素质等,没有扎     

残奥会冠军李端三级跳远单足跳技术的运动学分析

三级跳远是一项技术性很高的运动项目.实践证明运动员的单足跳是三级跳远中比较远的一跳,对运动成绩影响较大.单足跳阶段的技术参数的变化历来是研究的重点.采用录像解析方法对我国优秀全盲运动员李端的单足跳阶段的技术参数进行研究.结果发现:李端在起跳腿着地瞬间分腿角过大,离地瞬间分腿角过小;李端最大缓冲时膝角的缓冲幅度过小;蹬伸阶段蹬伸时机不当,单足跳阶段的重心腾起角过大;由于竞技水平的差异,李端的起跳时间过长;摆动腿的摆动角速度过小说明李端的摆动不积极.旨在为李端三级跳远起跳技术提供运动学依据和参考.     

我国男子竞走运动员的技术特征及生物力学分析

采用文献研究及生物力学分析等方法,对我国男子竞走运动员的技术进行分析,发现在1996年前的竞走规则和定义的影响下,我国男选手逐步形成了小步幅、快频率的技术特征。生物力学分析表明,髋的水平速度与摆动时间里高度相关,适当增加髋关节围绕身体垂直轴转动的速度,对提高步长有积极效果。控制足触地的角度和加强前摆着地技术的训练应引起重视。     

优秀男子50km竞走运动员扎西杨本在2019年全国竞走冠军赛的技术特点分析

扎西杨本是我国优秀竞走运动员,对其技术特点进行分析,找到薄弱环节,并提出针对性的建议。主要通过影像解析法分析扎西杨本的技术特点,发现扎西杨本步长偏小,倾向于缩小动作幅度来完成加速,常速状态下竞走技术较为合理,低速状态下技术舒展。着地技术佳,腾空时间符合竞走技术规范,后蹬力量有所不足,左右腿力量不均衡,加速时有前趴,核心力量需要加强。扎西杨本应该在后期的训练中注重髋关节的柔韧和力量,更好的体会向前"送髋"的技术,且平衡左右腿的力量。     

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。     

球类比赛中运动员的实时跟踪

使用计算机跟踪球场中的运动员，得到每名运动员的时序位置信息，是研究其体能和技、战术特点，辅助教练员进行科学训练的关键技术。运动场景中的目标跟踪方法有其特殊性。介绍了运动员实时跟踪的软件结构，研究了球类比赛中目标跟踪的特征选择、状态转换和实现方法，并以足球为例进行试验。试验结果证明，对多名运动员进行跟踪，算法是鲁棒而快速的。对多名运动员进行跟踪时，每秒帧数（fps）可以达到30。     

我国优秀女子竞走运动员技术特征研究

采用高速摄影机定点拍摄了2000年全国竞走锦标赛女子20 km竞走比赛前7名运动员的技术影片,并采用"TYF-2"型影片分析系统对影片进行解析,对运动员在比赛中程(10 km)的一个单步的各个阶段和各个技术环节进行了定量和定性的分析和研究.揭示了当今我国优秀女子竞走运动员的共性技术特征.结论我国优秀女子竞走运动员腾空时间为(48.8±9.8) ms;重心上下起伏距离为(6.0±1.3) cm,7名运动员身体重心的最高点均出现在支撑腿脚尖离地时,身体重心的最低点出现在垂直支撑时;前腿在触地瞬时的膝角为181.0°±2.0°,垂直支撑时膝角为185.7°±3.4°, 并保持157.0 ms的膝关节完全伸直状态,直至过渡到身体重心垂直面;优秀运动员均采用"足踵触地、踝关节背屈"滚动式着地技术,以及后蹬腿脚尖离地技术,符合当今世界竞走运动发展趋势.     

A Kinetic Analysis of the Ground Leg During Sprint Running

Abstract

Fifteen highly skilled sprinters were filmed while running at maximum velocity. The results were digitized and computer processed with interest focused on the muscle moments generated about the hip, knee, and ankle of the ground leg. Muscle activity about the hip consisted of extensor (concentric) dominance from foot descent, through foot strike, and into mid-support. Muscle dominance shifted to the hip flexors (eccentric) during mid-support and continued through takeoff. Muscle dominance at the knee demonstrated a pattern of flexor (eccentric, then concentric) dominance from foot descent through foot strike and into mid-support. Knee extensors (eccentric, then concentric) then achieved dominance through takeoff. During the later stages of takeoff, the dominance decreased or reversed briefly to flexor (eccentric) activity prior to a period of minimal activity following the toe-off position. From a period of minimal activity prior and subsequent to ground contact, the plantar flexors (eccentric, then concentric) of the foot were dominant throughout the ground phase. Qualitatively, the unexpected knee flexor dominance during foot strike was generated to limit the braking action created during this portion of ground contact. The unanticipated hip flexor dominance during takeoff served to rotate the upper body forward and into the approaching air phase. In addition, both of these actions allowed efficient use of the two-joint muscles of the leg during the critical phases of ground contact. Finally, the minimizing or reversing of the knee extensor dominance during the later stages of takeoff served to protect the joint from injury. Quantitatively, the magnitude of hip extensor/knee flexor activity during foot strike was significantly related (r = .70, p = .01) to the prior occurrences of related leg injury in the subjects.     

Ice hockey skate starts: a comparison of high and low calibre skaters

The forward skating start is a fundamental skill for ice hockey players, yet extremely challenging given the low traction of the ice surface. The technique for maximum skating acceleration of the body is not well understood. The aim of this study was to evaluate kinematic ice hockey skating start movement technique in relation to a skater’s skill level. A 10-camera motion capture system placed on the ice surface recorded “hybrid-V” skate start movement patterns of high and low calibre male ice hockey players (n = 7, 8, respectively). Participants’ lower body kinematics and estimated body centre of mass (CoM) movement during the first four steps were calculated. Both skate groups had similar lower body strength profiles, yet high calibre skaters achieved greater velocity; skating technique differences most likely explained the performance differences between the groups. Unlike over ground sprint start technique, skating starts showed greater concurrent hip abduction, external rotation and extension, presumably for ideal blade-to-ice push-off orientation for propulsion. Initial analysis revealed similar hip, knee and ankle joint gross movement patterns across skaters, however, further scrutiny of the data revealed that high calibre skaters achieved greater vertical CoM acceleration during each step that in turn allowed greater horizontal traction, forward propulsion, lower double-support times and, accordingly, faster starts with higher stride rates.     

Knee loading patterns in a simulated netball landing task

Abstract

The knee is a common site of injury in netball players. In this study, 10 high-performance netball players underwent a biomechanical assessment of their single leg landing technique whilst receiving a pass. Three-dimensional video and ground reaction force data were recorded using a motion analysis system. Net internal knee joint moments were calculated using a rigid body analysis and inverse dynamics. The kinematics of the support leg and front-on video footage was used to investigate whether players adhered to guidelines on safe and effective landing strategies. Results indicated that for most players the internal valgus moment was the largest frontal plane knee moment during the landing phase. This may reflect a relatively greater need to resist varus knee excursion or may be related to the kinematics of the hip. For 6 of the 10 players the rapid change to an internal knee valgus moment coincided with hip adduction. Since an increase in the magnitude of the internal valgus moment may increase the compressive forces in the medial compartment of the knee, further work should be undertaken to determine if a neuromuscular training intervention to improve the strength of the hip musculature may be beneficial for these players. A large relative excursion of the knee compared to the hip may indicate that these players had a greater reliance on the more distal segments of the lower extremity for the attenuation of the ground reaction forces. This information may be used to better understand potential knee injury mechanisms in netball players.     

中国精英女子赛艇运动员划桨技术特点分析

目的：以国家队和赛艇优势省队运动员为测试对象，总结分析我国精英女子赛艇运动员的划桨技术特点。方法：27名运动员参与本研究，利用"BioRow Tel"系统测试五种桨频（20、24、28、32、36桨/分）下的划桨技术，测试参数包括划桨节奏、桨叶轨迹、桨力特征等。结果：拉桨时间百分比随桨频的提高显著提高；入水角、出水角和划幅在中低桨频下非常稳定，但在接近比赛桨频时显著下降；抓水打滑和出水打滑均随桨频的增加而显著增加；与桨力相关的参数对桨频的变化相对不敏感。结论：我国运动员较为注重桨叶入水和拉桨前段，表现出的技术较好，而在拉桨后段特别是桨叶出水阶段暴露出的问题比较大；临近比赛桨频时的技术同中低桨频时相比存在比较明显的下降。训练中要解决好拉桨后段和桨叶出水的问题，并注重提高运动员在比赛桨频时的划桨技术。     

Kinetic function of the lower limbs during baseball tee-batting motion at different hitting-point heights

ABSTRACT

The aim of this study was to investigate the kinetic functions of the lower limbs at different hitting-point heights to provide key information for improving batting technique in baseball players. Three-dimensional coordinate data were acquired using a motion capture system (250 Hz) and ground reaction forces were measured using three force platforms (1000 Hz) in 22 male collegiate baseball players during tee-batting set at three different hitting-point heights (high, middle, and low). Kinetic data were used to calculate joint torque and mechanical work in the lower limbs by the inverse dynamics approach. The peak angular velocity of the lower trunk about the vertical axis was smaller under the low condition. The joint torques and mechanical works done by both hip adduction/abduction axes were different among the three conditions. These results indicate that hip adduction/abduction torques mainly contribute to a change in the rotational movement of the lower body about the vertical axis when adjusting for different hitting-point heights. In order to adjust for the low hitting-point height which would be difficult compared with other hitting-point heights, batters should focus on rotating the lower trunk slowly by increasing both hip abduction torques.