Abstract
Older adults modify their gait during dual-task (DT) walking while completing a cognitive task, but the underlying gait mechanics remain unclear. Many studies use unrealistic concurrent DTs involving sensory interference or discrete (non-continuous) cognitive demands. The purpose of this study was to investigate the influence of realistic DT demands on center of pressure (CoP) dynamics using continuous extemporaneous speech that mimics real-world cognitive demands in older adults. 15 older adults completed three conditions: seated speech (speaking continuously on a randomly assigned topic), walking only, and DT (walking while speaking continuously on a randomly assigned topic). Speech performance was analyzed by comparing seated speech and DT conditions, while spatiotemporal gait parameters, propulsion, and CoP displacement and velocity were analyzed by comparing walking-only and DT conditions. Walking trials were performed at a comfortable pace along a 10-meter pathway. Linear mixed-effects regression analysis revealed no changes to speech during DT compared with seated speech (all p > .17). In contrast, gait was significantly altered during DT compared with walking only, supporting the notion that realistic attentional demands interfere with gait in older adults, resulting in slower walking speed, shorter step length, and prolonged stance times (all p .22) indicates that lateral CoP dynamics were unchanged with DT demands, potentially through effective hip control or ankle strategies.