Dong Rui, Su Xinyu, Li Shichen, Ni Xindi, Liu Ye
School of Sport Science, Beijing Sport University, Beijing 100084, China.
Life (Basel). 2024 Nov 6;14(11):1433. doi: 10.3390/life14111433.
In forehand strokes with different grips in tennis, the forearm muscle activities, the distribution and attenuation of the impact loads, and the effects of the muscles on the impact load attenuation exhibited different characteristics. This study aimed to explore these characteristics by analyzing electromyography (EMG) and acceleration data, and comparing the differences between the Eastern and Western grips. Fourteen level II or above tennis players (ten males, aged 22.4 ± 3.6 years; four females, aged 19.8 ± 2.0 years) were recruited and instructed to perform forehand strokes using the Eastern and Western grips, respectively. The EMG of eight forearm muscles and the acceleration data at the ulnar and radial sides of the wrist and elbow were collected. The root mean square (RMS), the peaks of the impact load, the amplitude of impact load attenuation (AC), and the jerk value (Jerk) were calculated. The cross-correlation coefficients and time delays of EMG-EMG, EMG-AC, and EMG-jerk were obtained using the cross-correlation method. The results showed that in the Eastern grip group (group E), the RMS of the flexor carpi ulnaris (FCU) was significantly greater than that in the Western grip group (group W). In group E, the peaks of impact load, AC, and Jerk on the Y axis of the wrist ulnar side were all significantly higher than those in group W. The activity of the extensor digitorum commonis (EDC) had significantly different effects on the amplitude and rate of impact load attenuation at specific locations in different grips, especially at the elbow ( < 0.05). The conclusion indicated that the FCU exhibited higher levels of EMG activity in the Eastern grip. This grip responded to greater impact loads with more substantial and rapid attenuation on the wrist ulnar side. Furthermore, the EDC appeared to contribute more to the amplitude of impact load attenuation in the Western grip and to have a more significant influence on the rate of impact load attenuation in the Eastern grip, especially at the elbow. These results suggest that tennis players and coaches should pay more attention to improving the strength of the EDC and FCU, which can improve sports performance and comfort, as well as prevent sports injuries.
在网球中使用不同握法的正手击球时，前臂肌肉活动、冲击负荷的分布与衰减，以及肌肉对冲击负荷衰减的影响呈现出不同的特征。本研究旨在通过分析肌电图（EMG）和加速度数据，并比较东方式握法和西方式握法之间的差异，来探究这些特征。招募了14名二级及以上水平的网球运动员（10名男性，年龄22.4±3.6岁；4名女性，年龄19.8±2.0岁），并指导他们分别使用东方式握法和西方式握法进行正手击球。收集了八块前臂肌肉的肌电图以及手腕和肘部尺侧与桡侧的加速度数据。计算了均方根（RMS）、冲击负荷峰值、冲击负荷衰减幅度（AC）和急动值（Jerk）。使用互相关方法获得了EMG-EMG、EMG-AC和EMG-Jerk的互相关系数和时间延迟。结果表明，在东方式握法组（E组）中，尺侧腕屈肌（FCU）的RMS显著大于西方式握法组（W组）。在E组中，手腕尺侧Y轴上的冲击负荷峰值、AC和Jerk均显著高于W组。在不同握法的特定位置，尤其是在肘部，指总伸肌（EDC）的活动对冲击负荷衰减的幅度和速率有显著不同的影响（P<0.05）。结论表明，在东方式握法中FCU表现出更高水平的肌电图活动。这种握法在手腕尺侧对更大的冲击负荷有更显著且快速的衰减反应。此外，EDC似乎在西方式握法中对冲击负荷衰减幅度的贡献更大，而在东方式握法中对冲击负荷衰减速率有更显著的影响，尤其是在肘部。这些结果表明，网球运动员和教练应更加重视提高EDC和FCU的力量，这有助于提高运动表现和舒适度，同时预防运动损伤。
