对我国女子铁饼优秀运动员的技术分析

对参加2000年奥运会田径选拔赛的我国6名女子铁饼运动员最佳成绩的一次完整技术作为研究对象，采用爱捷运动录像快速反馈分析系统进行三维运动学分析，选取出手高度、出手速度、出手角度和躯干倾角等运动学指标，结合饼速变化特征和超越器械程度的相关影响因素，对6名运动员进行技术分析，结果表明：运动员出手时，同水平速度相比，垂直速度偏大；应加强以旋转节奏为主的专项练习；肩髋扭转角在左脚着地时达到最大；拉引角最好在左脚着地时为最大。     

从不同高度下落到不同硬度的地面上下肢关节的力学响应

本研究了人从30cm和60cm高度下落到两种不同硬度的地面，即木板地面和海绵垫上时下肢关节的力学响应。结果表明从两种高度下落到海绵垫上比落到木板地面时下肢关节的受力、力矩显减小，关节的角度变化显增加，从着地到落地停稳所用的时问显增加。各关节力矩是外力矩与肌肉力矩共同作用的结果，正确的落地技术应该是三个关节的力矩同时减小，掌握正确的落地技术的实质是掌握正确的肌肉被拉伸与收缩的顺序和大小。从30cm和60cm下落着地后，不论是何种地面条件。三个关节的力矩以髋关节力矩为最大，膝和踝关节肌肉是在髋关节控制下起互相协调作用。     

街舞文化

从美国到中国,街舞的发展坎坷曲折,度过了30多个年头．本文主要介绍国外街舞文化的种类及街舞进入中国后的发展,力图让更多的人认识街舞并关注街舞运动,并促进我国街舞文化的发展。     

我国速滑运动员膝关节肌群力特征研究

采用CYBEX6000等速测力仪,对53名(男30,女23)优秀速滑运动员膝关节屈伸肌群峰值力矩、总功、平均功率及其屈/伸比值进行了测试与研究.结果表明:双膝关节屈伸肌峰值力矩、总功随角速度递增而下降,平均率则升高;同一速度区屈伸肌群峰值力矩、总功及平均功率为伸肌大于屈肌;在不同速度区还伴有"优势交换"现象,低速区左侧伸肌显著大于右侧,高速区则以右侧伸肌增强为主.屈/伸肌比值随收缩速度增加略有提高,女子为46～68%,男子在56～76%之间.     

Lower extremity joint coupling variability during gait in young adults with and without chronic ankle instability

Chronic ankle instability (CAI) is a condition resulting from a lateral ankle sprain. Shank-rearfoot joint-coupling variability differences have been found in CAI patients; however, joint-coupling variability (VCV) of the ankle and proximal joints has not been explored. Our purpose was to analyse VCV in adults with and without CAI during gait. Four joint-coupling pairs were analysed: knee sagittal-ankle sagittal, knee sagittal-ankle frontal, hip frontal-ankle sagittal and hip frontal-ankle frontal. Twenty-seven adults participated (CAI:n = 13, Control:n = 14). Lower extremity kinematics were collected during walking (4.83 km/h) and jogging (9.66 km/h). Vector-coding was used to assess the stride-to-stride variability of four coupling pairs. During walking, CAI patients exhibited higher VCV than healthy controls for knee sagittal-ankle frontal in latter parts of stance thru mid-swing. When jogging, CAI patients demonstrated lower VCV with specific differences occurring across various intervals of gait. The increased knee sagittal-ankle frontal VCV in CAI patients during walking may indicate an adaptation to deal with the previously identified decrease in variability in transverse plane shank and frontal plane rearfoot coupling during walking; while the decreased ankle-knee and ankle-hip VCV identified in CAI patients during jogging may represent a more rigid, less adaptable sensorimotor system ambulating at a faster speed.     

The effect of low back pain on trunk muscle size/function and hip strength in elite football (soccer) players

ABSTRACT

Low back pain (LBP) is a common problem in football (soccer) players. The effect of LBP on the trunk and hip muscles in this group is unknown. The relationship between LBP and trunk muscle size and function in football players across the preseason was examined. A secondary aim was to assess hip muscle strength. Twenty-five elite soccer players participated in the study, with assessments conducted on 23 players at both the start and end of the preseason. LBP was assessed with questionnaires and ultrasound imaging was used to assess size and function of trunk muscles at the start and end of preseason. Dynamometry was used to assess hip muscle strength at the start of the preseason. At the start of the preseason, 28% of players reported the presence of LBP and this was associated with reduced size of the multifidus, increased contraction of the transversus abdominis and multifidus muscles. LBP decreased across the preseason, and size of the multifidus muscle improved over the preseason. Ability to contract the abdominal and multifidus muscles did not alter across the preseason. Asymmetry in hip adductor and abductor muscle strength was found between players with and without LBP. Identifying modifiable factors in players with LBP may allow development of more targeted preseason rehabilitation programmes.     

上海优秀男子青少年中跑运动员髋、膝关节等速肌力测试分析

通过对男子青少年中跑运动员进行髋、膝关节等速肌力测试,发现男子青少年中跑运动员髋、膝关节肌力特点及薄弱肌群。方法：对16名上海优秀男子青少年中跑运动员进行髋、膝关节单侧等速向心60°／s×6和240°／s×6测试记录测试峰力矩、最大功率、屈伸肌峰力矩比值。结果：髋关节屈肌峰力矩和相对峰力矩在两个速度存在显著差异（P〈0．05）,伸肌峰力矩和相对峰力矩两个速度存在高度显著差异（P〈0．01）,屈伸肌峰力矩比值存在显著差异（P〈0．05）,膝关节屈肌峰力矩及相对峰力矩无差异,而伸肌峰力矩和相对峰力矩在两个速度存在显著差异（P〈0．05）,屈伸肌峰力矩比值无差异。研究对象髋关节屈肌最大功率和相对最大功率在两个速度存在高度显著差异（P〈0．01）,伸肌最大功率和相对最大功率存在显著差异（P〈0．05）,膝关节屈伸肌最大功率和相对最大功率在两个速度存在高度显著差异（P〈0．01）。结论：髋关节随测试速度增加最大力矩呈现下降趋势,高速测试时峰力矩屈／伸值下降,髋关节屈肌力量需加强;膝关节伸肌峰力矩随测试速度增加减小,屈肌及峰力矩屈／伸值变化不明显。     

短跑途中跑中髋关节的作用分析

短跑是田径中最悠久的运动项目,是重要的基础项目。髋关节作为人体躯干与下肢连接的关节,在短跑的过程中起着重要作用。尽管髋关节在短跑中的重要地位已经得到应有的重视,但对髋关节在跑步过程中的认识仍有待不断深化。文章的研究目的就是对髋关节在短跑途中跑一个周期各阶段所起的作用进行分析,以期待对短跑的运动训练有指导和借鉴意义。文章通过对几本田径经典教材和关于短跑的数十篇最新研究成果的研究整理,对短跑途中跑各阶段中髋关节的运动状态,肌肉收缩状态做了详细的梳理,分析了期间髋关节的作用。     

我国优秀女子竞走运动员髋关节运动技术环节存在问题剖析

依据近几年国际竞走赛事中的统计可以发现，1996年新的竞走规则的实施，对我国竞走运动员的技术造成了巨大冲击，国际竞走界对“小步幅、高步频”竞走技术风格已经从有争议转变为不接受，国际赛场上不断有我国运动员被判罚出场的现象。针对我国运动员比赛中容易出现的技术犯规应重点研究髋关节运动技术，首次应用立体定点定机摄像方法对2003年全国竞走冠军赛女子10km比赛进行拍摄，选取前8名运动员作为研究对象，对我国优秀女子竞走运动员的髋关节运动技术进行研究，剖析运动员髋关节运动技术环节存在的问题，以引起教练员、运动员对髋关节运动技术的重视。     

重力式膝伸肌力量训练器械动力传动凸轮轮廓设计

通过实验获得人体膝伸肌等动向心收缩的力矩-角度特征曲线，然后，采用工作位法，在一定范围内对伸膝力矩-角度特征曲线进行模拟，获得器械工作凸轮的力臂值和轮径值，完成膝伸肌动力传动凸轮轮廓的设计。设计凸轮提供的阻力矩更符合人体膝伸力矩，解决了器械的全载负荷问题和因起始力矩过大产生可利用惯性、肌肉易疲劳和器械噪声等一系列问题。设计具有普遍适用性，使用的工作位法适用同类器械动力传动凸轮轮廓的设计。