国内优秀艺术体操运动员旋转难度起动技术的生物力学分析

Biomechanical Analysis of Starting Techniques of Rotation Difficulty of Elite Chinese Rhythmic Gymnasts

旋转类身体难度是艺术体操成套动作中获得高分的重要因素,同时也是当今高水平运动员竞技能力的重要体现。起动技术是艺术体操旋转难度动作中的关键技术,直接影响甚至是决定旋转难度的完成质量。因此,对旋转起动技术的生物力学研究是旋转难度技术研究的关键。综合运用Motion红外高速运动捕捉系统、三维测力台,对国家队2名优秀艺术体操运动员的阿提丢转体、后搬腿转体和俯平衡转体3类旋转难度的起动技术进行运动学与动力学分析,以探究其技术特征,进一步明确旋转难度的正确技术模式,为旋转技术训练提供理论依据与参考。研究认为:旋转难度起动缓冲蓄力时间大于蹬伸时间,较长的缓冲蓄力时间可为准确的发力和重心的快速移动奠定基础;旋转起动阶段,应根据不同旋转难度的技术特征,选择适宜的身体姿态角;在摆臂蹬地阶段,手臂挥摆在动力腿离地前应适时制动,摆臂角速度的变化量与难度形成时旋转初始角速度成正相关;合理的重心移动技术是影响蹬伸阶段蹬地发力和旋转轴形成的关键技术。

Objectives: Rotation Difficulty is an important factor in winning high points in rhythmic gymnastics routines,and also an important manifestation of the competitiveness of today’s elite athletes. The starting technique is the key in the rotation difficulty of rhythmic gymnastics,and will directly affect or even determine its completion quality. Therefore,a biomechanical research of the starting technique in rotation is of great significance to the study of rotation difficulty techniques. Using the infrared high-speed motion capture system and three-dimensional force platform,this study made kinematics and dynamics analysis of the starting techniques of three types of rotation difficulties which were performed by two elite Chinese rhythmic gymnasts on the national team,namely,attitude,split with support and Penche ( leg in back split,rotation on flat foot),in order to explore the technical characteristics and further define the correct technical mode of rotation difficulty,so as to provide theoretical basis and reference for rotation technique training. Results: The buffer time for the starting of rotation difficulty is longer than that of pedaling and stretching,and a longer buffer phase paves the way for accurate power generation and rapid movement of center of gravity. In the starting phase of rotation,the proper angels of body posture should be selected according to the technical characteristics of different rotation difficulties. In the pedaling and stretching phase,the arms should be timely braked before the power legs leave the ground. The changes of angular velocity of the pedaling arms in horizontal plane is positively correlated with the initial angular velocity of trunk rotation when the posture is formed. A reasonable movement technique of COM is the key technique that affects the rhythmic gymnast’s kicking force and the formation of rotation axis.