Institute of Physical Education, Health & Leisure Studies, National Cheng Kung University, Tainan, Taiwan.
Physical Education Office, Kun Shan University, Tainan, Taiwan.
Sports Biomech. 2021 Jun;20(4):419-430. doi: 10.1080/14763141.2018.1560492. Epub 2019 Feb 7.
This study determined the effect of skill level (ITN 3 vs. ITN 8) on the tennis serve biomechanics and analysed the impact of forearm fatigue on dominant arm mechanisms between the two groups (expert vs. non-expert tennis players). The motion capture system with 17 reflective markers attached on anatomic landmarks of the participant was used for data collection. A total of 12 expert and 11 non-expert tennis players performed the required serving tasks. The ball speed of the expert group was significantly faster than that of the non-expert group during non-fatigued and fatigued states ( < 0.001). The wrist radial/ulnar deviation angle at impact was significantly different between non-fatigued and fatigued states for top-spin ( = 0.030) and flat serves ( = 0.018). A significant increase in extensor carpi ulnaris (ECU) and extensor carpi radialis (ECR) muscle activity during extension ( < 0.010) was observed, with that of the ECU being an ulnar deviation. Both the ECU and ECR might contribute to wrist joint and racket handle stability for the coming acceleration and impact while fatigue occurs. Fatigue might substantially influence non-experts' dominant forearms because of the significantly different elbow joint angles and dominant arm syndromes they displayed as compared with the experts.
本研究旨在确定技能水平（ITN3 与 ITN8）对网球发球生物力学的影响，并分析两组（专家和非专家网球运动员）中前臂疲劳对优势手臂机制的影响。使用附有 17 个反射标记的运动捕捉系统来采集参与者的解剖标志数据。共有 12 名专家和 11 名非专家网球运动员完成了所需的发球任务。在非疲劳和疲劳状态下，专家组的球速明显快于非专家组（<0.001）。在旋转发球和平发球时，非疲劳和疲劳状态下的腕关节桡骨/尺骨偏转角有显著差异（=0.030）。在伸展过程中，伸腕肌（ECU）和伸腕肌（ECR）的肌肉活动明显增加（<0.010），其中 ECU 是尺骨偏斜。当疲劳发生时，ECU 和 ECR 可能有助于腕关节和球拍柄的稳定性，为即将到来的加速和冲击做准备。由于非专家表现出明显不同的肘关节角度和优势手臂综合征，因此疲劳可能会对他们的优势前臂产生实质性影响。
