影响我国少年跳高运动员成绩的技术因素分析及训练对策

采用三维摄像法对影响我国16～17岁少年男女跳高运动员成绩获得的各技术因素的运动学分析,指出了我国优秀少年跳高运动员技术水平现状和存在的问题,并提出了发展对策.     

对我国男子优秀跳高运动员起跳技术的三维运动学分析

采用两台SONY高速摄像机对我国部分男子优秀背越式跳高运动员进行赛场同步拍摄,运用爱捷运动录像反馈系统进行解析.结果表明:在起跳开始瞬间,身体重心的垂直速度较低;起跳腿的髋、膝、踝3关节蹬伸不充分,摆动腿的摆动速度和高度较低,助跑水平速度未能合理地转化为起跳的垂直速度.起跳的垂直速度是影响我国男子跳高运动员成绩的主要因素.     

对我国新老两代女子铅球运动员最后用力技术的对比分析

运用三维摄影解析和运动学的方法,对我国女子铅球优秀运动员李梅菊等在2003年石家庄全国田径大奖赛上的最后用力阶段的技术进行运动学分析并与前国手李梅素、黄志红和隋新梅进行了对比,发现我国新老女子铅球运动员的最后用力技术存在差异.     

对我国优秀男子三级跳远运动员跨步跳起跳三时相运动学参数的研究

运用定点高速录像(250帧/ s)的方法,对我高优秀男子三级跳远运动员跨步跳起跳过程中三时相(着地、缓冲、蹬伸)运动学参数进行了定量分析.分析结果表明:跨步跳起跳过程中,着地角、起跳幅度、着地时重心高度、离地时重心高度、离地时两大腿夹角对跨步跳离地时水平速度影响较大,是造成跨步跳阶段水平速度损失大的主要原因.我国优秀男子三级跳远运动员跨步跳起跳过程中,过分屈膝,蹬伸迟、不充分,摆动动作消极,不能有效地提高腾起初速度,提高起跳效果.     

背越式跳高起跳阶段摆动腿摆动的运动学特征及对起跳效果的影响

运用影片拍摄及解析的方法对参加第8届全国运动会男子跳高比赛前10名运动员在起跳过程中摆动腿摆动的运动学进行了分析。结果表明：在起跳过程中，摆动腿摆动角度速度最大值为腾起垂直初速度呈非常显著性的正相关，与蹬伸时间呈显著性的负相关，同时，摆动腿的摆动使身体重心高度呈上升趋势。另外，运动员在起跳过程中普遍存在着摆动腿的摆速和摆幅偏小的问题，从而影响了起跳效果。     

Could knee joint mechanics during the golf swing be contributing to chronic knee injuries in professional golfers?

ABSTRACT

Full three-dimensional movements and external moments in golfers’ knees and the possible involvement in injuries have not been evaluated using motion capture at high sample frequencies. This study measured joint angles and external moments around the three anatomical axes in both knees of 10 professional golfers performing golf drives whilst standing on two force plates in a motion capture laboratory. Significant differences were found in the knee joint moments between the lead and trail limbs for the peak values and throughout all stages during the swing phase. A significantly higher net abduction moment impulse was seen in the trail limb compared with the lead limb (?0.518 vs. ?0.135 Nms.kg^?1), indicating greater loading over the whole swing, which could contribute to knee lateral compartment or anterior cruciate ligament injuries. A significant correlation (r = ?0.85) between clubhead speed at ball contact and maximum joint moment was found, with the largest correlations being found for joint moments at the top of the backswing event and at the end of the follow-through. Therefore, although knee moments can contribute to high clubhead speeds, the large moments and impulses suggest that they may also contribute to chronic knee injuries or exacerbate existing conditions.     

基于ADAMS的微型管道机器人三维实体运动仿真

在ADAMS环境下,建立了小口径六轮机器人运动模型,创建了相应的仿真环境,并进行了三维实体运动仿真。通过对质心处的位移、速度、加速度曲线以及对弹簧的力和驱动力矩曲线的分析,证明该六轮机器人在直管道内的移动具有基本的运动稳定性和可行性。为了解机器人工作空间的形态和大小提供了一种实验手段。以管道内受限微型机器人的运动学模型为例进行了运动学分析。结果表明,该行走机构具有结构紧凑、驱动效率高、安装方便、工作可靠、成本低廉等特点。     

男子标枪运动员“第二支撑制动现象”的运动学特征分析

借助KS— 16mm高速摄影机 ,对我国第五届大学生运动会前 8名男子标枪运动员最后用力双支撑阶段的投掷动作进行了拍摄。研究结果 :把髋理解为“第二支撑制动环节” ,有助于对该环节的重视 ,更有助于了解其在最后用力过程中产生制动所发挥的作用。“第二支撑制动现象”的出现 ,对上肢的“鞭打”动作 (投掷效果 )有着直接的影响     

中外优秀女子100m栏运动员运动学参数比较分析

运用运动生物力学研究方法,分析我国3名优秀女子100m栏运动员的各项运动学参数,并与国内外优秀运动员相比较,研究结果显示:我国运动员与世界级优秀运动员相比,在加速跑能力、达到最高速度能力以及保持较高分栏速度能力方面还有一定的差距。并在跨栏步技术上存在跨栏腿蹬伸不足、下栏距离长、身体重心起伏大等问题。     

Effects of load on ground reaction force and lower limb kinematics during concentric squats

The purpose of this study was to examine the effects of external load on vertical ground reaction force, and linear and angular kinematics, during squats. Eight males aged 22.1?±?0.8 years performed maximal concentric squats using loads ranging from 7 to 70% of one-repetition maximum on a force plate while linear barbell velocity and the angular kinematics of the hip, knee and ankle were recorded. Maximum, average and angle-specific values were recorded. The ground reaction force ranged from 1.67?±?0.20 to 3.21?±?0.29 times body weight and increased significantly as external load increased (P?<?0.05). Bar linear velocity ranged from 0.54?±?0.11 to 2.50?±?0.50?m?·?s^?1 and decreased significantly with increasing external load (P?<?0.05). Hip, knee and ankle angles at maximum ground reaction force were affected by external load (P?<?0.05). The force?–?barbell velocity curves were fitted using linear models with coefficients (r ²) ranging from 0.59 to 0.96. The results suggest that maximal force exertion during squat exercises is not achieved at the same position of the lower body as external load is increased. In contrast, joint velocity coordination does not change as load is increased. The force?–?velocity relationship was linear and independent from the set of data used for its determination.