Modulations of muscle activity in the elderly during transient lateral floor transition with handgrip holding and temporal instructions

Abstract

: This study aimed to investigate the lower limb musclesʼ postural dynamic re-sponse to handgrip holding and temporal instruction of floorʼs lateral movement during transient lateral floor transition in the elderly. The study included 11 healthy elderly male subjects with a mean age of 75.9(cid:156)7.0 years. There were four conditions used in combina-tion with handgrip holding and temporal instruction during transient lateral floor transition. Lower limb muscle activities before and after lateral floor transition were measured using an electromyogram. The results revealed that the maximum muscle activities de-pendent on the direction of disturbance were reduced in the temporal instruction condi-tion. Furthermore, most of the leg musclesʼ resting and maximal activities were decreased in the handgrip holding condition. In conclusion, it was revealed that standing balance could be maintained with a small amount of activity by handgrip holding and temporal instruction.