木工上半身肌肉负荷影响的差异性定量研究

目的在特定实验任务中,对专业木工和初学者木工的表面肌电图信号进行差异性分析,为木工提供合理的工作策略指导其减少工作相关肌肉骨骼疾患(WMSDs)的发病率。方法本研究模拟木工的工作任务,测定21名专业木工和21名初学者木工的4块前臂肌肉(肱桡肌、尺侧腕伸肌、尺侧腕屈肌、桡侧腕屈肌),3块肩部肌肉(前部三角肌、中部三角肌、后部三角肌)和斜方肌的表面肌电信号(sEMG)差异,并以经验水平、工作任务和肌肉类别为对比项对表面肌电信号的平均值和峰值统计学分析。结果专业木工和初学者木工之间sEMG的均值和峰值无显著性差异,初学者木工8块肌肉都表现出较高的肌肉活动水平;从局部肌肉的sEMG均值和峰值来看,木工工作任务对前部三角肌和后部三角肌造成较大肌肉负荷;经验水平、工作任务和肌肉类别对专业木工和初学者木工上半身的肌肉负荷的影响有显著差异。结论经验对木工的肩膀肌肉负荷有较大缓解作用,对降低木工工作时的肌肉疲劳度和损伤风险度具有积极作用。

Quantifying Differences in Muscle Exposures of Upper Body in Different Experience Levels of Carpenters

Objective Construction industry workers have a high rate of work related musculoskeletal disorders (WMSDs) incidence.Carpentry is one trade at particularly high risk,with muscular demands being one of the causal factors for injury.Studies have illustrated that muscle activity differences exist between expert and novice workers.Methods This study investigated differences in twenty-one expert and twenty-one novice carpenters'shoulder and forearm muscles.Surface EMG readings of 4 forearm muscles (brachioradialis(BR),extensor carpi ulnaris (ECU),flexor carpi ulnaris (FCU),flexor carpi radialis (FCR)),3 shoulder muscles (anterior deltoid (AD),middle deltoid (MD),and posterior deltoid (PD)),and the trapezius (TRAP.) were measured.Results Mean and peak values were quantified and compared across experience level,task,and muscle type.Novices tended to exhibit higher levels of muscle activity for both tasks and all muscles although not significantly.Experiences,tasks and muscles significantly affected sEMG measures for both forearm and shoulder muscles.An interaction of experience level by muscle was also found to be significant on mean and peak for the shoulder muscles and mean for the forearm muscles.Conclusion These findings indicate that differences may exist in the way experts and novices perform a task and that training and expert work strategies may be useful in preventing risk of injury for workers early in their work cycle.