Investigating the Impact of the Hoe handle Length and Angle on the Shoulder and Arm Muscle Activity during Manual Farming Activities

Hoe is an important hand tool used by the farmers across India for land preparation and digging work. Continuous and repeated use of hoe in awkward posture results in severe work-related musculoskeletal distress. The main objective of this study was to investigate the effect of hoe handle length and angle on arm and shoulder muscle engagement and subject preference. For this purpose, two modified hoes with different handle lengths were utilized to perform land preparation work and their muscle engagement was compared with a traditional land preparation activity. Ten volunteers participated in this experimental study and their muscle activities on biceps brachii (bilateral) and trapezius muscle (bilateral) during continuous land preparation process were recorded using surface electromyography (sEMG) sensors. Subjective discomfort rating was carried out using Borg’s CR-10 scale. Results revealed that Model 1 with medium handle length had reduced the muscle activation on arm and shoulders. Subjective preference results revealed that biceps brachii muscles followed by trapezius left muscle had high rate of discomfort during the land preparation work.