Modeling of Temporal Change in Stride Length of Healthy Elderly and Young Adults during Dual Task Walk

Abstract

This study investigates the temporal relation between the presence of recall question and stride length under dual-task walk using autoregressive exogenous (ARX) model. The ARX model is developed to estimate the response of stride length during the dualtalk walk. Each stride length is measured by a toe-mounted inertial sensor. Ninety elderly subjects performed a recall question like the names of Japanese prefectures during 50 [m] walk, and eleven younger ones performed a more difficult task during 100 [m] walk. Most of step responses estimated by ARX model showed the local minimum value in the stride length immediately after the start of recall question. The time from the start of recall question to the local minimum is around 2.5 [s] and has no significance between elderly subjects (n=23) and younger ones (n=8). The recall question while walk causes rapid decrease in stride length and may increase of risk of fall.