Study on Kinematic Characteristics of Tennis Serve Technology under Different Serving Modes

Abstract

Background and Aim: Tennis serve has an absolutely important position on the tennis court. The serving mode of topspin, flat stroke, and side spin cannot be completely distinguished and mastered by most Chinese athletes, and one of the effective ways to improve the technique of serving technology is to measure and analyze the serving technology from the perspective of biomechanics. This study aimed to analyze the biomechanical characteristics of the different service techniques. Materials and Methods: The participants of the study Xi'an Sports Institute eight secondary athletes, with two high-speed cameras eight two athletes serve three different biomechanical characteristics of image information acquisition, through the APAS data analysis software for video analysis and data processing, get three kinds of athletes serve technology. By comparing the kinematic parameters of the three serving techniques, the regular content of the three serving techniques is revealed. Result: The height of the highest point of the three serve throws of the eight players are 3.126±0.110m,3.258±0.052m, and 3.167±0.153m. The hit position heights are 2.904±0.044m,3.051±0.131m, and 2.920±0.085m. The center of gravity displacement at the hit position averaged 0.44m,0.474m, and 0.471m. The height of the center of the ball is 1.321±0.030m,1.345±0.035m and 1.325±0.035m. The center of gravity height at the hitting moment is 1.435±0.035m,1.505±0.051m and 1.461±0.049m. At the hitting time, the results of the three serves of the eight players are as follows: The right knee angle was 173.916deg, 140.732deg, and 159.772deg. The right shoulder vertical axis has angles of 87.041deg, 92.867deg, and 86.898deg. The right shoulder angles are 41.09deg,72.847deg and 34.113deg, 77.572deg, 122.674deg, and 131.052deg from the right elbow, 151.894deg, 111.125deg and 129.412deg from the right wrist. The velocity of the right shoulder joint was 1.31m/s, 1.369m/s and 1.483 m/s. The velocity of the right elbow joint was 1.788m/s, 2.443m/s and 2.136 m/s. The velocity of the right wrist was 2.265m/s, 3.257m/s and 3.256 m/s. The velocity of the ball is 17.476m/s, 38.215m/s, and 21.327m/s. Conclusion: When the same player applies different serving techniques, the smaller the difference between the highest point of the ball and the position of the ball, the better the serve effect. There are some differences between the hitting moment and the body (head) position. The center of gravity displacement trajectory is the same, but the height of the highest, the second side rotation, and the lowest topspin. The Angle of the knee and right shoulder vertical axis vary similarly, and the angular acceleration of the elbow and the minimum Angle of the wrist are almost the same, but the Angle of the shoulder is somewhat different, and the size of the Angle is related to the position of the shot. The speed curves of the right shoulder, right elbow, and right wrist all have the same trajectory, but the speed of the same joint of the three service techniques is somewhat different. Cause a different serve effect.