Objective The purpose of the study was to explore the fatigue changes of workers during manual ma -terials handling and the influence of handling time and workload.Methods In this study,the experiment task was loading and unloading on a product line and 32 healthy participants were recruited to perform the 2.5-hour task manually.BIOPAC MP150 and Borg's RPE scale were used to collect surface Electromyography(sEMG),Electrocar-diogram(ECG)and subjective data.Results With the increase of handling time and workload,the time and fre-quency domain indices of sEMG,iEMG and MF increased and decreased respectively,both erector spine and trapezius showed fatigue symptoms and the latter was more serious.Heart rate showed an upward trend in the early stage of han-dling task,and then tended to be stable.Heart rate variability increased along with the handling time and was positive-ly affected by workload.Besides,the subjective results showed a linear relationship with the workload.Conclusion The three techniques that this study adopted showed validity and consistency in measuring and evaluating fatigue caused by manual materials handling.And handling time and workload had significant influence on worker 's fatigue which reminded us to put forward reasonable handling limit and rest schedule.%目的 探索手工搬运作业过程中机体的疲劳规律以及作业时间、负荷对机体疲劳的影响.方法以流水线端上料、下料作业为背景,选择32名健康被试进行2.5小时手工搬运作业,使用BIOPAC MP150生理记录仪和Borg's RPE量表记录被试的表面肌电、心电和主观疲劳数据.结果 随作业时间延长与负荷增加,表面肌电的时域指标iEMG与频域指标MF分别呈现上升与下降趋势,竖脊肌与斜方肌出现疲劳症状,后者更为严重.心率在搬运作业前期呈现上升趋势,随后趋于平稳;心率变异性呈整体上升趋势,并受到作业负荷的正向影响.主观疲劳随作业时间延长呈上升趋势,与作业负荷具有一定的线性关系.结论 选取的三种测量方法对手工搬运作业疲劳的评价基本一致,能够有效表征机体疲劳状态随作业时间、负荷的变化规律.作业时间、负荷对手工搬运作业者的疲劳状态具有显著的正向影响,应考虑制定合理的搬运作业限值和休息制度.
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