Center for the Research of Sports Psychology and Biomechanics, China Institute of Sport Science, Beijing, Beijing, China.
Graduate Department, Capital University of Physical Education and Sports, Beijing, Beijing, China.
PeerJ. 2024 Oct 30;12:e18410. doi: 10.7717/peerj.18410. eCollection 2024.
Tennis, the second-largest ball game in the world, has a particularly wide audience. To date, little research has been conducted on the biomechanics of female serves.
The purpose of this study was to capture the key moments by using 1,000 frames/s high-speed video analysis, to analyze the kinematics of the serving techniques of national athletes and provincial athletes, to determine the differences between the two levels of athletes, and to provide theoretical references for the improvement of scientific training level.
Ten female athletes were selected as participants for this study, five of whom are national athletes, and the other are provincial athletes. Three-dimensional filming techniques were employed to capture videos of the first and second serve techniques. Simi Motion was applied to obtain the 3D kinematic data. Statistical analyses were performed using IBM SPSS Statistics 27.0, and Mann-Whitney U tests were conducted to determine differences between groups.
Significant differences in kinematics were found between national and provincial athletes. At the moment of the left knee's minimum flexion (T2), in the first serve, national athletes had a smaller shoulder-hip vertical plane angle (-18.281 ± 6.142° . -25.631 ± 3.497°; = 0.047) and a larger hip vertical plane rotation angle (-9.378 ± 4.263° . -0.470 ± 4.724°; = 0.047). In the second serve, national athletes had a smaller hip horizontal plane rotation angle (-1.720 ± 4.683° . 24.146 ± 24.014°; = 0.047) but a larger hip vertical plane rotation angle (-11.553 ± 1.949° . -0.422 ± 4.958°; = 0.009). At the moment of impact (T4), in the second serve, national athletes' batting position (0.296 ± 0.088 m . 0.446 ± 0.094 m; = 0.047) was further back. Additionally, in the second serve, national athletes consistently had their body center of gravity further back at T2 (-0.106 ± 0.052 m . -0.018 ± 0.048 m; = 0.028), T3 (0.002 ± 0.038 m . 0.132 ± 0.039 m; = 0.009), and T4 (0.073 ± 0.050 m . 0.217 ± 0.034 m; = 0.009).
The results of this study indicated several significant kinematic differences between national and provincial athletes, these variations were noted in the shoulder, hip, and body center of gravity. In summary, for the overall first and second serves, it is recommended that national athletes increase the horizontal plane angle of the shoulders and hips at T2, whereas provincial athletes decrease the horizontal plane angle of the shoulder-hip. In addition, provincial athletes need to increase the vertical plane angle of the hip joint, so that the top of the hip can be increased more, and provincial athletes need to be careful not to have the center of gravity too far in front of the body at T2, T3, and T4, so that it can hit the ball at a higher position to increase the swing speed.
网球是世界上第二大球类运动，拥有特别广泛的受众群体。迄今为止，针对女性发球的生物力学研究还很少。
本研究旨在通过使用 1000 帧/秒的高速视频分析来捕捉关键瞬间，分析国家级运动员和省级运动员发球技术的运动学，确定两个水平运动员之间的差异，并为提高科学训练水平提供理论参考。
本研究选取了 10 名女性运动员作为参与者，其中 5 名为国家级运动员，其余为省级运动员。使用三维拍摄技术拍摄第一发球和第二发球技术的视频。应用 Simi Motion 获取 3D 运动学数据。使用 IBM SPSS Statistics 27.0 进行统计分析，采用 Mann-Whitney U 检验进行组间差异分析。
国家级运动员和省级运动员在运动学方面存在显著差异。在左膝最小屈曲时刻（T2），在第一发球中，国家级运动员的肩髋垂直面角度较小（-18.281 ± 6.142°，-25.631 ± 3.497°； = 0.047），髋关节垂直面旋转角度较大（-9.378 ± 4.263°，-0.470 ± 4.724°； = 0.047）。在第二发球中，国家级运动员的髋关节水平面旋转角度较小（-1.720 ± 4.683°，24.146 ± 24.014°； = 0.047），但髋关节垂直面旋转角度较大（-11.553 ± 1.949°，-0.422 ± 4.958°； = 0.009）。在击球时刻（T4），在第二发球中，国家级运动员的击球位置（0.296 ± 0.088 m，0.446 ± 0.094 m； = 0.047）更靠后。此外，在第二发球中，国家级运动员在 T2（-0.106 ± 0.052 m，-0.018 ± 0.048 m； = 0.028）、T3（0.002 ± 0.038 m，0.132 ± 0.039 m； = 0.009）和 T4（0.073 ± 0.050 m，0.217 ± 0.034 m； = 0.009）时，身体重心更靠后。
本研究结果表明，国家级运动员和省级运动员在肩部、髋关节和身体重心方面存在一些显著的运动学差异。总之，对于整体的一发和二发，建议国家级运动员增加 T2 时肩髋的水平角度，而省级运动员则减少肩髋的水平角度。此外，省级运动员需要增加髋关节的垂直面角度，使髋关节顶部能够增加更多，同时需要注意在 T2、T3 和 T4 时不要让重心过于靠前，以便能够在更高的位置击球，从而增加挥拍速度。
