Muscles activities at two different work area boundaries during sedentary work

Abstract

The aim of this study is to investigate the effects on upper limb and lower back muscles activities at two different work area boundaries during sedentary work. Subjects consisted of 10 males (age 27.7±5.42) and 10 females (age 27.5±5.91) with no history of musculoskeletal injury or back problem at the time of participation. Surface electromyography (EMG) signal were recorded from the right and left Levator Scapulae, Upper Trapezius, Anterior Deltoid and Erector Spinae which are known as the weaken and tighten muscles due to musculoskeletal disorders (MSD). The EMG signal was processed and normalized in the form of % MVC for analysis. The overall results indicated that the upper limb and lower back muscles activities increased significantly when performing work at the far boundary work area. The muscle activity at the far boundary work area is averagely 17% greater than at the near boundary work area. The result of independent sample t-test showed that the gender effects found to be significant at the far boundary work area.