Quick picking and heavy lifting are the most common problems in current workplaces. They can cause lumbar muscle damage. The operator then must spend energy, time, and money for recovery or rehabilitation. To solve this problem, we developed a passive-type assistive suit using air mesh material, elastic band, and wire. To determine the strength support effect of the passive-type assistive suit, electromyography (EMG) was performed for eight muscles and the maximum voluntary contraction (MVC) was analyzed when lifting weights of 0%, 15%, and 30% of the subject’s weight in a Semisquat motion. Results showed that MVC increased as the weight of the heavy object increased. However, its increase was not proportional to the decrease in MVC according to the presence or absence of assistive suits or the weight of the heavy object. The highest MVC was observed for the erector spinae muscle under all conditions. The greatest decrease in MVC according to working clothes was measured for the vastus lateralis muscle (lifting: 17.7±2.95%, lowering: 18.3±0.55%). These results show that lifting work performed while wearing a passive-type assistive suit using wires and elastic bands is effective in assisting muscle activity.

Farming is a typical task that includes repetitive tasks, incomplete working positions, and weight work, along with exposure to a number of musculoskeletal diseases and harmful factors. Therefore, in this study, work clothes were developed for older agricultural workers exposed to musculoskeletal diseases and alienated from the medical system. Work clothes can help in repetitive cropping and support the load on the work, preventing and mitigating farmers" diseases. To verify the effectiveness of the developed clothing, six men in their 20s were evaluated for muscle usage before and after wearing the clothing in two ways: stoop lifting and squat lifting. The results of this study showed that the mass of most muscles, except the gastrocnemius muscle, was reduced during lifting operations by stoop lifting after wearing work clothes. The reason why the gastrocnemius was more activated was that the ankle joint was greatly activated by dorsal flexion. For squatting and lifting, most of the muscle usage was reduced. In future research, we want to analyze the muscle characteristics of actual agricultural workers on wearing work clothes.