Maintaining dynamic balance is essential during walking, with foot-placement playing a critical role. Dual-task studies analyzing steady-state walking with cognitive loads found that healthy adults prioritize cognitive task performance at the expense of maintaining their balance control. However, few studies have focused on the influence of a cognitive task on the strategy used to recover balance when faced with unexpected changes to foot-placement and if the strategy used is influenced by the task difficulty. The purpose of this study was to assess how individuals prioritize cognitive resources to recover from a mediolateral foot-placement perturbation while walking when performing cognitive tasks of increasing difficulty. Young healthy adults (n=15) walked under steady-state unperturbed and perturbed conditions with increasingly challenging cognitive loads. Medial and lateral foot-placement perturbations were applied just prior heel strike during random steps. While balance control decreased during perturbed relative to unperturbed walking, the addition of a cognitive load had little effect on balance control. The strategy used to recover from the perturbation, as measured by peak joint moments at the ankle and hip, was also unaffected by the addition of a cognitive load. However, the correct cognitive response rate decreased between unperturbed and perturbed walking trials. These results suggest that, in contrast to unperturbed steady-state walking, young adults prioritize maintaining their balance control over the performance of a cognitive task when faced with foot-placement perturbations. This work highlights the flexibility of task-prioritization in young adults and provides the basis for future studies to determine differences in neurologically impaired populations.
