Occupational Biomechanics Laboratory, Department of Kinesiology, McMaster University, Hamilton, ON, Canada, L8S 4K1.
Occupational Biomechanics Laboratory, Department of Kinesiology, McMaster University, Hamilton, ON, Canada, L8S 4K1.
Appl Ergon. 2019 Feb;75:250-256. doi: 10.1016/j.apergo.2018.11.001. Epub 2018 Nov 17.
Repetitive work is common in the modern workplace and the effects are often studied using fatigue protocols; however, there is evidence that the manner in which fatigue develops impacts the kinematic and muscular response to reduced physical capacity. The purpose of this study was to simultaneously evaluate muscular and kinematic adaptations during fatiguing, repetitive work until exhaustion. We measured muscle activity in 13 muscles in the shoulder and trunk, and captured full body kinematics while participants completed simulated, repetitive work tasks. Every 12 min, reference data were collected to quantify fatigue. This sequence continued until they reached the termination criteria. Participants displayed significant signs of muscle fatigue, loss of strength and increased perceived fatigue (p < 0.05). Analysis revealed a significant effect of time on posture and muscle activity that was both task and time dependent, and variable both between and within individuals. Participants were able to compensate for reduced physical capacity and maintain task performance through coordinated compensation strategies.
重复性工作在现代工作场所很常见，其影响通常通过疲劳协议进行研究；然而，有证据表明，疲劳发展的方式会影响运动学和肌肉对身体能力下降的反应。本研究的目的是同时评估疲劳、重复性工作直到力竭过程中的肌肉和运动学适应性。我们测量了肩部和躯干 13 块肌肉的肌肉活动，并在参与者完成模拟、重复性工作任务时捕捉全身运动学。每 12 分钟收集一次参考数据以量化疲劳。这个序列一直持续到达到终止标准。参与者表现出明显的肌肉疲劳、力量丧失和疲劳感增加的迹象（p < 0.05）。分析显示，时间对姿势和肌肉活动有显著影响，且既依赖于任务又依赖于时间，并且在个体之间和个体内部都存在差异。参与者能够通过协调补偿策略来补偿身体能力的下降并保持任务绩效。
