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目的探讨表面肌电和心电技术评价不同手工搬举下腰背部竖脊肌的劳动负荷,以期获得最佳搬举技术。方法30名大学生志愿者在实验室模拟手工搬举作业,分别测定和分析蹲举、背举和半蹲举的左、右侧胸10水平竖脊肌(LT10、RT10)和腰3水平竖脊肌(LL3、RL3)表面肌电、心率和Borg量表分值的变化情况。结果3种搬举技术下,男性LT10、RT10和女性LL3、RL3竖脊肌表面肌电幅度均方根值的最大随意收缩百分比(percentage of maximum voluntary electrical activation,MVE%)均较休息时高(P<0.05)。男性LT10、LL3和女性RT10、LT10的MVE%在蹲举时最高(P<0.05)。女性RL3的MVE%在半蹲举时最低(P<0.05),而女性LL3的MVE%在背举时最低(P<0.05)。男性LT10和女性LT10、LL3的中位频率(MF)均高于休息时的值(P<0.05),而男性、女性RL3的MF值均低于休息时的值(P<0.05)。3种搬举技术下,男性、女性的MF值无统计学意义。与休息时比较,3种搬举技术下,男性、女性心率均高于休息时的值(P<0.05)。男性、女性在背举时心率最低(P<0.05),蹲举时心率最高(P<0.05)。3种搬举技术下,Borg量表分值无统计学意义。结论相同搬举负荷时,蹲举是不推荐的搬举。尽管背举时肌肉和心血管应激程度较低,但是竖脊肌薄,在生物力学上力矩短,我们不提倡使用它来搬举重物。基于上述原因,我们认为半蹲举是一种适宜的搬举技术,此时肌肉和心血管应激处于较低水平。
Objective To investigate the surface electromyography and electrocardiogram (ECG) technique to evaluate the labor load of different posterior erector spinae muscles in order to obtain the best lifting technique. Methods Thirty college volunteers simulated hand-lifting exercises in the laboratory to measure and analyze the left and right thorax 10-level erector spinae (LT10, RT10) and waist 3-level erector Muscle (LL3, RL3) surface EMG, heart rate and Borg scale scores changes. Results The percentage of maximum voluntary electrical activation (MVE%) of rms amplitude in male LT10, RT10 and female LL3 and RL3 was higher than that at rest P <0.05). MVE% of male LT10, LL3 and female RT10, LT10 were highest at crouching (P <0.05). Female MVE% of RL3 was the lowest in squatting (P <0.05), while MVE% of female LL3 was the lowest in back lifting (P <0.05). The median frequency (MF) of male LT10 and female LT10 and LL3 were higher than those at rest (P <0.05). The MF of RL3 in both male and female was lower than that at rest (P <0.05). Under the three removal techniques, the MF of men and women had no statistical significance. Compared with the rest, the heart rate of the male and female was higher than that of the rest (P <0.05) under the three lifting techniques. The heart rate of males and females was the lowest (P <0.05), while the heart rate was the highest in squats (P <0.05). Under the three lifting techniques, Borg scale scores were not statistically significant. Conclusions The same lift lift, squat is not recommended move. Despite lower muscular and cardiovascular stress on the back, the erector spinae is thin and has a short biomechanical moment. We do not advocate using it to lift heavy objects. For the above reasons, we think that squatting is a suitable lifting technique in which muscle and cardiovascular stress are at a low level.