Medial part thickness of wearable device affecting running motion

Abstract This paper reports negative effects on runner’s motions which are supported by an exoskeleton attached to his/her lower limbs. A wearable assistive device has generally been developed to support motions of a wearer, while the device may disturb wearer’s motions due to physical features, including expanded his/her body outline and device’s weight. The expanded outline can exert adverse influence that limits range of motion of a wearer. In this paper, we focus on lower limb motions of a runner who puts an exoskeleton on his/her lower limbs to receive physical assistance. We simulated influence of medial parts of the exoskeleton on running through experiments with seven runners wearing one of three couples of rectangular-shaped light blocks (10 mm, 20 mm or 30 mm in thickness) on the medial sides of both thighs. These blocks increased step width but the 30 mm-thick blocks only increased net running heat rates by 6.05 bpm compared with that of running without blocks. This result shows that a wearable device which is equipped with components less than 20 mm-thick on each medial part of a runner’s thigh has little detrimental effects on running motions.