Electromyographic pattern (EMG) of the lower limb muscles during running in weightlessness on a gravity simulator

Abstract

Introduction Muscles and bone loss are two of the most serious impediments to extended human spaceflights. It seems that impact loading, bone stress and muscular work rate undergone during locomotion are important cues for maintaining bone and muscular mass (McCrory et al., 2002). We have developed a gravity simulator on a treadmill in an attempt to reproduce in weightlessness the mechanics of locomotion on Earth. On the gravity simulator, the traction force, equivalent to the action of gravity, is only exerted on the trunk whereas the limb segments remain in weightlessness. On the contrary, during terrestrial locomotion, the swing movements of the limb segments are aided by the action of gravity. The goal of the present study is to compare the electromyographic pattern (EMG) of the main muscular groups of the lower limb while running on the gravity simulator and on Earth.