表面肌电和心电评价手工搬举作业工间休息的实验研究  

Experimental simulated study on the break for manual lifting task by surface electromyography and electrocardiogram

作　　者：王正伦[1] 吴磊[1] 宋挺博[1] 陈飙[1] 何丽华[2] 王生[2] 杨磊[1] 

机构地区：[1]华中科技大学同济医学院公共卫生学院劳动卫生与环境卫生学系,环境与健康教育部重点实验室,武汉430030 [2]北京大学公共卫生学院劳动卫生与环境卫生学系

出　　处：《中华劳动卫生职业病杂志》2011年第3期167-170,共4页Chinese Journal of Industrial Hygiene and Occupational Diseases

基　　金：国家“十一五”科技支撑项目资助（2006BAI06B08）

摘　　要：目的研究手工搬举作业的工间休息时间。方法30名大学生志愿者从事模拟的蹲举、背举和半蹲举手工搬举作业，分别测定他们在工间休息时左、右侧胸10（LT10、RT10）和腰3（LL3、RL3）竖脊肌的肌电及其心电，分析最大随意收缩肌电百分比（percentage of maximum voluntary electrical activation, MVE% ）、中位频率（median frequency，MF）及心率（heartrate，HR），评价负荷恢复状况。结果15min工间休息内，男性被测试者4个部位竖脊肌肌电MVE％均在5min内恢复至静息水平，且91．8％在2min内恢复；而女性被测试者除Rk和LL3 MVE％在半蹲举活动后未恢复外，其余肌肉MVE％均在3min内恢复，且67．8％在2min内恢复。男性被测试者除RL，竖脊肌肌电MF在蹲举和背举后未恢复外，其余MF均在10min内恢复，且74．9％在2min内恢复。女性被测试者竖脊肌肌电MF均在8min内恢复，且83．4％在2min内恢复。在3种搬举活动结束后20min休息时段内，男、女被测试者各部位竖脊肌MVE％和MF均恢复到静息水平；男、女被测试者心率分别在14、5rain恢复到静息水平。结论在负荷为25％MVC，持续时间为4．5min的3种搬举活动中，就局部肌肉负荷的恢复而言，15min休息仅保证绝大多数竖脊肌恢复；就全身负荷恢复而言，15min休息可保证心率完全恢复到静息水平。Objective To investigate the recovery duration of manual lifting tasks. Methods 30 college student volunteers with gender equally distributed were involved in the simulated stoop-, squart- and semisquart-lifting tasks in the laboratory. Signals of electromyography （ EMG ） at the back muscles （ left and right thorax m. erector spinae, LTI0 and RTl0; left and right lumbar m. erector spinae, LL3 and RL3 ） and electrocardiography （ECG） were recorded during the rest intervals. The percentage of maximum voluntary electrical activation（ MVE% ）, EMG median frequency （MF）, and heart rate （HR） were analyzed to predict the recovery time required. Results During the break, MVE% at 4 back muscles of all the male subjects were recovered to resting level within 5 minutes and 91.8% were within 2 minutes. Except for RL3 after squat- and stoop-lifting task, the MVE% of female subjects went back to resting level within 3 minutes and 67.8% were within 2 minutes. The MF of male subjects were recovered in 10 minutes and 74.9% within 2 minutes, with the exception of RL3 after stoop- and squat- lifting tasks. All the female MF were recovered in 8 minutes and 83.4% were within 2 minutes. However, during the last 20 minute break after the lifting tasks, the MVE% and MF of all male and female subjects were recovered, while HR came back to resting level within 14 and 5 minutes, respectively. Conclusions For the three manual lifting tasks with 25% MVC workload lasting for 4.5 min, a break of 15 minutes is sufficient for most erectors spinae to recover from local muscle load. However, in terms of the HR, a break of 15 minutes is enough for the recovery of systematic load.

关 键 词：工作负荷量 肌电描记术 心电描记术 休息 

分 类 号：R1[医药卫生—公共卫生与预防医学]