不同落点网球侧上旋发球技术的运动学对比分析

目的:探索不同落点(T内角、Body追身和Wide外角)网球侧上旋发球技术动作的运动学规律。方法:采用2台三维高速摄像机拍摄10名网球运动员侧上旋发球技术动作,使用北京体育大学视讯解析系统采集运动学参数,对原始数据进行平滑和归一化处理等(Fc=10)。结果:1)抛球引拍阶段:抛球时左肩水平投影角呈显著性差异,左肩、右肩和左膝关节角速度变量呈显著性相关(R=0.82),站位方式无显著性差异;2)"挠背"阶段:不同落点发球时发力顺序协调一致,由下至上逐步将力量传递至击球点;3)挥拍击球阶段:击球时刻不同落点间分速度和击球角度差异性显著,外角侧旋>追身侧旋>内角侧旋,内角上旋>追身上旋>外角上旋,外角Angle>追身Angle>内角Angle。击球点高度与身高的倍数为外角(1.32)、追身(1.25)和内角(1.21),击球点由内至外逐渐向右偏移;4)随挥阶段:击球后重心位移和速度分量未出现显著性差异,膝关节角度变化均值39.7±1.8°。结论:我国高校网球二级运动员亟需储备发球隐蔽性、击球点空间位置、挥拍轨迹和击球速度分量等方面的意识体系。应当继续以运动生物力学为手段加强网球各类型发球技术动作、各环节运动特征和发球所致损伤因素等进行系统化和精细化研究。

Comparative Kinematical Analysis of Tennis Kick Serve with Different Locations

Objective:To explore the kinematics rules of tennis kick serve movements with different locations(T Inner Angle,Body Pursuit and Wide Outer Angle).Methods:Two 3 D highspeed cameras were used to film the kick serve technique of 10 tennis players.The kinematics data of the service technology movements were collected by the video analysis system of Beijing Sport University,and the original data were smoothed and normalized(Fc=10).Results:1)backstroke stage:the horizontal projection angle of the left shoulder was significantly different.The angular velocity variables of the left shoulder,right shoulder and left knee joint were significantly correlated(R=0.82),and there was no significant difference in the standing mode;2)"back scratching"stage:when serving to different locations,the order of power was consistent,and the power was transferred to the hitting point step by step from the bottom to the top;3)swing batting stage:the minute speed and batting angle difference between different locations at the impact moment was significant.The external angle side-rotation>chasing the body side rotation>internal angle side rotation,the internal angle top-rotation>chasing the body side rotation>external angle,the external angle>chasing the body angle>internal angle.The multiples of hitting point height and height were external angle(1.32),chasing body(1.25)and internal angle(1.21).The hitting point gradually moved to the right from inside to outside;4)swing stage:there was no significant difference in the center of gravity moving distance and center of gravity velocity component after hitting the ball,and the average change of knee angle after hitting the ball 39.7±1.8°.Conclusion:The conscious system of secondary tennis college player in China needs to reserve the concealment of the serve,the spatial position of the hitting point,the swing trajectory and the weight of the hitting ball.Scholars should continue to use the method of sports biomechanics as a means to strengthen the systematic and refined research on various types of teeing techniques,various sports characteristics and damage factors caused by serve.