Kinematic Analysis On The Serve Technique Of Excellent Man Tennis Back-ups In Jiangsu Province

In this paper, six outstanding junior tennis player of the Jiangsu's junior sports school were choosen to be the research object. By using the two Mega high-speed cameras with shooting frequency of 300 frames per secound, exposure time of 1/2000 second synchronization, we collected the three-dimensional moving images information, and adopted the German SIMI-Motion Video Image Analysis System to analysis the images. And using the methods of research such as literature, video analysis and statistics to analysis their kinematic parameters when they are serving. Then we find some little fault about their serve Technique. Details need to be adjusted and the serve technology need to be made more perfect. Besides, this research also provide some parameters to the coaches for training improve. Not noly Enhance the theoretical and practical significance of junior, but for the development of junior in Jiangsu Province. Study results showed that: (1)To all of them six, the head drop of the ball is too large, and the ball's track is almost Vertical after be thrown in the air.(2)When the first phrase ending, their left hip action was not obvious, the ranger of the shoulders backward, knee flexion and the side bow are all not big enough, but the bow back full.(3) The players' leg stretch rate is magnitude smaller, the swing effect of the left arm need to be improved.(4)The movement of their upper body do a good whipping action when serving, reasonable and consistent, from the large joints to the small joints. But the whole body do a bad one in the serving process. Use less leg power. Shoulder axis of rotation in the sagittal plane range is not enough, racket swing magnitude too small.(5)The players'angle is nearly 90 degrees when they hit the ball, the racket face is a bit back, wrist movements appear after the hitting, the use of the body gravitational energy is not sufficient, and somebody's elbow had not been straight, hitting point is lower, upper explosive force is better, but the body's follow-up action after hitting is inadequate.