CONTRIBUTIONS OF ARM’S MAJOR MUSCLES DURING MANUAL WHEELCHAIR PROPULSION IN RANDOM SPEED BY HEALTHY PERSONS

Abstract

Propulsion of manual wheelchair demands physical strength of upper limb and users would be exposed to injuries and muscle fatigue for long-term. Therefore, power assist system operated on surface electromyography (sEMG) signal from arm muscles developed aggressively few years back. However, an important prerequisite for selecting which muscles as reference is to understand each muscles contribution during contact and recovery phases. The primary purpose of this study was to investigate motor unit action potentials (MUAP) for Biceps Brachii (BIC), Triceps Brachii (TRI), Extensor Carpi (EXT) and Flexor Carpi (FIX) muscle groups located in human arm during both phases. MUAPPEAK in every contact and recovery phases for each muscle groups were recorded from 13 subjects. Then, mean and standard deviation (SD) value determined. Result shows that the highest mean value belongs to Flexor Carpi muscle group 2.85V and highest standard deviation (SD) ±0.28V for Triceps Brachii. Mean value indicate which muscle contributed most to perform activities in contact and recovery phase, meanwhile SD is for propulsion speed. These finding would provide useful guidelines or suggestions for research related EMG-based interface instrumented wheelchair.