标枪出手瞬间的运动生物力学分析

运用运动生物力学的三维DLT研究方法,得知在标枪离手之前,手的速度逐渐减小,标枪的速度逐渐增大,并在离手瞬间标枪速度达到最大值.通过运用建立起的人工神经网络模型,对标枪出手速度与身体环节相关参数指标的关系进行模拟分析,并利用训练好的网络模型进行了标枪出手速度预测,得到了较好的预测结果.预测结果反映出手、肘、肩环节决定枪的出手速度,要提高标枪的远度必须提高手、肘、肩及人体重心的移动速度及做好鞭打动作.     

男子1500m跑时身体各环节输出功的初步研究

运动高速摄影和跑台气体代谢法对男子中长跑运动员进行了研究.通过测定运动员1500 m跑步过程中身体各环节输出功,发现运动员身体各环节输出功的比例关系为:摆动腿占比例最大,其次是支撑腿,上肢和躯干的输出功的比例相当,头部所占比例很小.运动员跑步过程中,环节内和环节之间存在能量转换,且环节之间能量转换是主要的.     

男子l500m跑时身体各环节输出功的初步研究

运动高速摄影和跑台气体代谢法对男子中长跑运动员进行了研究。通过测定运动员1500m跑步过程中身体各环节输出功,发现运动员身体各环节输出功的比例关系为;摆动腿占比例最大,其次是支撑腿,上肢和躯干的输出功的比例相当,头部所占比例很小。运动员跑步过程中,环节内和环节之间存在能量转换,且环节之间能量转换是主要的。     

铅球最后用力阶段的运动生物力学分析

最后用力是推铅球的技术的关键环节。因为此阶段对成绩的影响起决定性作用(约占85%左右)。那么,如何提高最后用力的效果和获得最大的出手速度呢?为了说明问题,首先从(没有滑步的)原地推铅球的最后出手速度分析起。一、对原地推铅球的出手速度的讨论1.公式的推导为了简单起见,设运动员在作原地推铅球时,身体各环节加给铅球的力为F,铅球     

推铅球过程中肌电、支撑力的测试及初步研究

目前,使用科学仪器直接测量推铅球过程中的肌电变化和支撑力变化所见资料很少,这无疑会影响我们对推铅球技术的正确认识。本文就是在这种思想指导下,用日本进口四导肌电遥测仪和两台三维测力台对推铅球过程中肌肉的肌电变化和支撑力变化进行了测试,来探求推铅球过程中身体各环节运动的内在联系、肌肉发达和它与地面之间反应的支撑力变化所表现出来的推铅球技术结构与身体各环节之间的关系。     

投掷铁饼的基本原理

一、决定投掷远度的因素 A.出手的速度;B.出手的角度;C.出手的高度;D.器械本身特有的空气动力学因素(指标枪与铁饼的差别)。二、成功地完成投掷动作与下面的因素有关 (一)正确的投掷技术 1.适当的身体平衡和姿势:这是保证获得最大的动作幅度、充分发挥身体各部分最大效能的前提。     

标枪运动员常见损伤的致因及防治措施

标枪属于轻器械过头顶类项目。看似简单的投掷过程,却对运动员的身体和技术有着复杂的要求。从助跑到交叉步,再到最后的标枪出手,整个技术动作的流畅性尤为重要。而身体动力链中各运动环节同样需要协调一致、一气呵成:举枪助跑产生水平速度;交叉步跑时肩关节后伸是主动     

优秀运动员投标枪技术的运动学分析

对美国奥林匹克队优秀标枪运动员在比赛和训练中拍摄了高速影片,拍摄速度为100格/秒。用摄影机的内时标纠正拍摄速度。共拍摄了28人次,男15人。女13人。影片在解析仪上处理,用小型计算机处理的运动学数据共有六个运动学参数;出手角、攻角、仰角、出手高度,前脚到边线距离及出手速度。出手速度是按出手后30毫秒内的平均速度计算的。运用多元线性回归方程和交互相关评定了各运动学参数之间的差异。研究证明,男子组和女子组之间在出手速度和出手高度上有显著性差异,其它四个参数没有显著性差异。男子平均枪速为29.3米/秒,女子为21.8米/秒,平均成绩分别为84.5米和55米。该文研究发现男女组的枪速和飞行的实际距离之间都没有显著相关。还发     

我国女子铁饼运动员最后用力阶段技术分析

掷铁饼最后用力阶段环节枝术是指在掷铁饼的最后加速阶段,身体各环节为将铁饼以最快的出手初速度和适宜的角度掷出,而采用的动作方法。本文运用三维摄像方法对我国8名优秀女子掷铁饼运动员的最后用力技术进行研究,利用三维运动快速解析系统,获取数据,经皮尔森相关分析获得我国优秀女子掷铁饼运动员最后用力技术的各个环节中与铁饼成绩相关密切的指标。     

影响铅球运动距离的各要素分析

根据力学公式数据采集实验法、数理统计的方法、文献资料法,全面阐述和分析了影响铅球运动距离各要素之间的关系,并提出在满足出手速度这一首要因素的情况下,调整出手高度和出手角度的建议。     

Comparison of biomechanical characteristics between male and female elite fast bowlers

This study investigated ball release speed and performance kinematics between elite male and female cricket fast bowlers. Fifty-five kinematic parameters were collected for 20 male and 20 female elite fast bowlers. Group means were analysed statistically using an independent samples approach to identify differences. Significant differences were found between: ball release speed; run-up speed; the kinematics at back foot contact (BFC), front foot contact (FFC), and ball release (BR); and the timings between these key instants. These results indicate that the female bowlers generated less whole body linear momentum during the run-up than the males. The male bowlers also utilised a technique between BFC and FFC which more efficiently maintained linear momentum compared to the females. As a consequence of this difference in linear momentum at FFC, the females typically adopted a technique more akin to throwing where ball release speed was contributed to by both the whole body angular momentum and the large rotator muscles used to rotate the pelvis and torso segments about the longitudinal axis. This knowledge is likely to be useful in the coaching of female fast bowlers although future studies are required to understand the effects of anthropometric and strength constraints on fast bowling performance.     

Timing of ball release in overarm throws affects ball speed in unskilled but not skilled individuals

We tested the hypothesis that variability in the timing of ball release in overarm throws affects ball speed. Nine unskilled and six skilled throwers made 30 throws fast and accurately from a sitting and standing position. Angular positions of finger and arm segments were recorded with search-coils at 1000 Hz; ball speed was measured with a radar gun. The time of ball release from the fingertips was measured with respect to seven arm kinematic reference points. Mean timing windows for ball release were 28?ms for unskilled throwers and 7?ms for skilled throwers. Mixed-model analyses of variance showed that a there was a statistically significant relationship between ball speed and the timing of ball release in unskilled throwers, but not in skilled throwers. This was presumably due to the difference in variability of the timing of ball release between the two groups. In contrast, skilled throwers showed a relationship between ball speed and peak forearm angular velocity (one measure of arm speed). We conclude that although variability in the timing of ball release can affect ball speed, this is only a major factor in unskilled throwers. When skilled throwers throw fast, variability in ball speed is due to variability in arm speed.     

Timing of ball release in overarm throws affects ball speed in unskilled but not skilled individuals

We tested the hypothesis that variability in the timing of ball release in overarm throws affects ball speed. Nine unskilled and six skilled throwers made 30 throws fast and accurately from a sitting and standing position. Angular positions of finger and arm segments were recorded with search-coils at 1000 Hz; ball speed was measured with a radar gun. The time of ball release from the fingertips was measured with respect to seven arm kinematic reference points. Mean timing windows for ball release were 28 ms for unskilled throwers and 7 ms for skilled throwers. Mixed-model analyses of variance showed that a there was a statistically significant relationship between ball speed and the timing of ball release in unskilled throwers, but not in skilled throwers. This was presumably due to the difference in variability of the timing of ball release between the two groups. In contrast, skilled throwers showed a relationship between ball speed and peak forearm angular velocity (one measure of arm speed). We conclude that although variability in the timing of ball release can affect ball speed, this is only a major factor in unskilled throwers. When skilled throwers throw fast, variability in ball speed is due to variability in arm speed.     

The relationship between discus throwing performance and combinations of selected technical parameters

The aim of this study was to determine the relationship between discus throwing performance and the following technical parameters: hip–shoulder and shoulder–arm separation, trunk forward–backward tilt, throwing-arm elevation angles, and the absolute and relative throwing procedure phase times. Videographic data of 51 male and 53 female discus throwers' competitive performances were captured during major meets. The three-dimensional coordinates of 21 body landmarks and the discus were obtained for each thrower's best trial using direct linear transformation. The technical parameters were reduced from the three-dimensional data at six critical instants during the throwing procedure. Hierarchical stepwise multiple regression analyses were performed to determine the relative influence of linear combinations of the technical parameters on discus throwing performance. Specific techniques associated with linear combinations of certain technical parameters were identified using canonical correlations. Males and females were analysed separately. Suggestions for controlling the height of release and the vertical component of the speed of release using an effective technique are made.     

The relationship between discus throwing performance and combinations of selected technical parameters

The aim of this study was to determine the relationship between discus throwing performance and the following technical parameters: hip-shoulder and shoulder-arm separation, trunk forward-backward tilt, throwing-arm elevation angles, and the absolute and relative throwing procedure phase times. Videographic data of 51 male and 53 female discus throwers' competitive performances were captured during major meets. The three-dimensional coordinates of 21 body landmarks and the discus were obtained for each thrower's best trial using direct linear transformation. The technical parameters were reduced from the three-dimensional data at six critical instants during the throwing procedure. Hierarchical stepwise multiple regression analyses were performed to determine the relative influence of linear combinations of the technical parameters on discus throwing performance. Specific techniques associated with linear combinations of certain technical parameters were identified using canonical correlations. Males and females were analysed separately. Suggestions for controlling the height of release and the vertical component of the speed of release using an effective technique are made.     

优秀女子铅球运动员在投掷过程中对外输出机械能及其与动作技术关系的研究

应用三维摄影和三维运动录像分析系统,从人体对外输出机械能角度对掷铅球技术进行了研究。发现滑步阶段对外输出的能量以平动动能为主,过渡阶段输出的机械能量少。最后用力准备阶段输出的动能,机械能达到最大值,最手用力加速阶段输出的机械能总量下降。对主要环节输出能量和运动成绩进行了相关分析,发现躯干输出能量与铅球成绩有密切关系,躯干运动在铅球技术中具有重要作用。     

The control of upper body segment speed and velocity during the golf swing

Understanding the dynamics of upper body motion during the downswing is an important step in determining the control strategies required for a successful and repeatable golf swing. The purpose of this study was to examine the relationship between head, thorax, and pelvis motion, during the downswing of professional golfers. Three-dimensional data were collected for 14 male professional golfers (age 27 +/- 8 years, golf-playing experience 13.3 +/- 8 years) using an optical motion analysis system. The amplitude and timing of peak speed and peak velocities were calculated for the head, thorax, and pelvis during the downswing. Cross-correlation analysis was used to examine the strength of coupling and phasing between and within segments. The results indicated the thorax segment had the highest peak speeds and peak velocities for the upper body during the downswing. A strong coupling relationship was evident between the thorax and pelvis (average R2 = 0.92 across all directions), while the head and thorax showed a much more variable relationship (average R2 = 0.76 across all directions). The strong coupling between the thorax and pelvis is possibly a method for simplifying the motor control strategy used during the downswing, and a way of ensuring consistent motor patterns.     

基于运动人体热舒适的体育场馆环境温度参数优化研究

体育场馆作为体育教学的主要场所,其热环境直接影响到运动人体的舒适健康和运动效果。为了获得运动人体热舒适,需维持人体与环境热交换之间产热和散热的动态传热平衡。夏季舒适的体育场馆热环境通常要消耗大量的空调能耗制冷,由此可见,体育场馆具有巨大的节能潜力。以1200名在西安某高校体育场馆内进行羽毛球活动的大学生为研究对象,监测大学生经过羽毛球训练后的生理参数以及对热舒适、疲劳感觉的评价,利用SPSS 23.0和ORIGIN进行数据统计分析,采用描述性统计、多元回归、方差分析等统计方法分析客观和主观数据之间的相互关系,建立不同环境温度工况对运动人体热舒适的定量影响关系。研究结果表明,环境温度对学生的舒适感受、疲劳感觉认知以及生理参数存在交互作用,形成热感觉满意率、疲劳感觉满意率与环境温度之间的定量影响关系。同时,以运动人体平均皮肤温度、血压、心率三类评价因子表征生理参数,进而反映体育场馆环境温度对其的显著性差异。通过兼顾运动人体热舒适和疲劳感觉满意率的综合影响,提出舒适的环境温度参数推荐范围,较国家标准中的室内空调环境温度的低限制值提高了2℃,有效降低了体育建筑夏季空调系统能耗。     

Kinematic analysis of shot-putting performed by wheelchair athletes of different medical classes

The aim of this study was to identify those kinematic characteristics that are most closely related to an athlete's medical classification and measured distance of a put. Two S-VHS camcorders (60 fields per second) were used to record the performance of 17 males of different classes. Each participant performed six trials and the best trial for each was selected for analysis. Three-dimensional kinematics of the shot and upper body segments at the instant of release and during the forward thrust (delivery) were determined. The average speeds and angles of the shot at release for different classes (5.3-7.8 ms -1 and 21.2 to 34.4°, respectively) were smaller than those exhibited by elite male able-bodied throwers. The height of the shot at release, the angular speed of the upper arm at release, the range of motion of the shoulder girdle during the delivery, and the average angular speeds of the trunk, shoulder girdle and upper arm during the delivery, were all significantly correlated with both the classification and measured distance ( P ? 0.05). The results indicate the importance of achieving a high average angular speed for each upper body segment during the delivery.