Abstract
Long time desk work causes cervico-omo-brachial syndrome and lumbago by muscle fatigue. In this research, we aim to develop a system that supports the workers to avoid cervico-omo-brachial syndrome and lumbago by decreasing their muscle fatigues. The system monitors the worker's muscle activities using the surface electromyography (sEMG) sensors, and supports the workers using self-adjustable desk and chair. APDF (Amplitude Probability Density Function) is applied to the evaluation index of muscle activities.As a fundamental experiment, muscle activities of workers invarious postures are evaluated by APDF analysis of sEMG data.