我国女子铁饼运动员李艳凤掷铁饼技术特征的研究

A Research on the Technique Characteristics of Chinese Women's Discus Thrower LI Yan-feng

以我国女子铁饼运动员李艳凤为研究对象,运用文献资料法、专家访谈法、生物力学测试法和数理统计法对她的时间、空间和速度等技术特征进行分析,结果发现李艳凤动作幅度大,双支撑起转阶段起转速度低、预摆扭转小、时间短、下蹲大;单支撑旋转阶段铁饼快加速、旋转时间短,膝关节蹬伸速度快、幅度大、转动姿势低;腾空阶段技术时间短、肩髋扭转紧和速度快,加速用力早、着地姿势高;转换阶段铁饼处在加速状态,转换速度快、用力早、旋转幅度大、着地重心高;最后用力阶段李艳凤以旋转用力为主,用力时间短、速度快,出手角度低、速度快、出手高;建议李艳凤双支撑旋转阶段增大肩髋角,减小投掷臂预摆幅度,提高技术稳定性。

In this paper,the methods of literature review,expert interview,bio-mechanical testing and mathematical statistics are applied to explore the discus throwing technique of Li Yan-feng,including the timing,space and velocity.The main conclusions are as follows： Li Yan-feng throw rotation range is large;Start velocity is low,swing small,time is short,and squat is low on the first double support stage;Rotate time is short,knee angle changes big,the extend velocity is high and CM is low on single support stage.Strength exertion is earlier,the swing is large,the CM is high and the right foot contacts the ground on flying stage;Li Yan-feng is on the course of velocity increase on the transition stage.The transitions velocity is high,the strength exertion is earlier,and foot width is large;Rotation is the mainly strength exertion means of Li Yan-feng and swing large.The velocity is high and throwing height is high on final stage.It proposes that Li Yan-feng can increase torso turn round,shorten rotation swing and improve technique performance stability.