The Effect of an Anticipated Perturbation on Gait Variability and Stability during Treadmill Walking in Young, Healthy Adults

Increased movement variability in quiet standing correlates with improved standing stability following a balance perturbation. It is unknown if this translates to gait. This study aimed to determine if increasing gait variability is a strategy to improve stability. We hypothesized that 1) spatio-temporal gait features will be more variable prior to an expected perturbation than during unperturbed walking, and 2) increased spatio-temporal gait variability pre-perturbation will correlate with improved stability post-perturbation. Sixteen healthy young adults completed 15 treadmill-walking trials under two conditions (unperturbed and an expected perturbation). Short- and long-term variability of step length, width, and time were calculated. Stability was defined as the number of steps to restabilization post-perturbation. Long-term step width variability was significantly higher pre-perturbation compared to unperturbed walking. There was no significant relationship between pre-perturbation variability and post-perturbation restabilization. These findings suggest that participants increased movement variability as an exploratory strategy in anticipation of a perturbation.M.Sc