RELATIONSHIP BETWEEN MUSCLE COACTIVATION, AROUSAL, AND STABILITY METRICS DURING PERTURBED GAIT

Abstract

Falls are a health risk to people of all ages. One mechanism that may increase the chances of a fall is a feed-forward increased co-contraction, or stiffening strategy. Another mechanism that influences fall risk is perceived levels of arousal. High arousal can negatively affect rate of force development by increasing muscle co-contraction. We studied the potential relationship between arousal, co-contraction, and stability metrics to get a better understanding of the mechanism behind falls. This study found that there was a significant increase in co-contraction and margins of stability from the preperturbation to the perturbation step. However, there were weak to no correlations between arousal and either co-contraction or margins of stability. Therefore, perceived arousal doesn’t seem to be a strong predictor of co-contraction or fall risk.