Forman Davis A, Forman Garrick N, Robathan Jason, Holmes Michael W R
Faculty of Science, University of Ontario Institute of Technology, Oshawa, ON, Canada.
Faculty of Applied Health Sciences, Brock University, St. Catharines, ON, Canada.
J Electromyogr Kinesiol. 2019 Apr;45:53-60. doi: 10.1016/j.jelekin.2019.02.004. Epub 2019 Feb 19.
The purpose of this study was to examine forearm muscle activity during simultaneous execution of dual motor tasks; hand-gripping and wrist forces. Surface electromyography was recorded from eight muscles of the upper-limb: flexor carpi radialis, flexor carpi ulnaris, flexor digitorum superficialis, extensor carpi radialis, extensor carpi ulnaris, extensor digitorum, biceps brachii and triceps brachii. Participants were seated with their forearm supported in a neutral position with an adjustable force transducer placed on either the palmar or dorsal side of the hand (for palmar/dorsal forces). Participants performed trials of simultaneous handgrip and wrist forces of various magnitudes, ranging in intensity from 0 to 40% of their maximal voluntary contraction. Trials lasted 5 s and force and electromyography data were assessed. The wrist flexors provided greatest contributions to tasks dominated by palmar forces but exhibited very low muscle activity in dorsal dominant tasks. Wrist extensors were active at moderate-to-high levels across nearly all conditions and demonstrated greater activity than the wrist flexors during handgrip-dominant tasks. These findings suggest that the wrist extensors provide the greatest contribution to wrist stiffness in complex motor tasks, and highlight the importance of investigating forearm muscle recruitment strategies under dual task parameters.
本研究的目的是检查在同时执行双重运动任务（手握力和腕部力量）期间的前臂肌肉活动。从上肢的八块肌肉记录表面肌电图：桡侧腕屈肌、尺侧腕屈肌、指浅屈肌、桡侧腕伸肌、尺侧腕伸肌、指伸肌、肱二头肌和肱三头肌。参与者就座，前臂支撑在中立位置，在手掌或手背放置一个可调节的力传感器（用于测量掌侧/背侧力）。参与者进行了各种强度的同时手握力和腕部力量试验，强度范围为其最大自主收缩的0%至40%。试验持续5秒，并评估力和肌电图数据。腕屈肌在以掌侧力为主的任务中贡献最大，但在以背侧力为主的任务中肌肉活动非常低。腕伸肌在几乎所有情况下都处于中高水平的活动状态，并且在以手握力为主的任务中表现出比腕屈肌更大的活动。这些发现表明，在复杂的运动任务中，腕伸肌对腕部僵硬的贡献最大，并突出了在双重任务参数下研究前臂肌肉募集策略的重要性。
