Reciprocal influence of concurrent walking and cognitive testing on performance in older adults.

This study investigated how cognitive and walking performance are influenced when performed concurrently in older adults and what factors are associated with poorer dual-task responses. Using a dual-task study design, 217 subjects aged 74-85 years completed three information processing test conditions--(1) no test; (2) push-button simple reaction-time; and (3) visual-spatial decision reaction-time; and three walking test conditions--(1) seated; (2) walking over a 20m straight course; and (3) walking over 20m with a turn. Push-button and visual-spatial reaction-times increased approximately 21% and 6%, respectively, while walking compared to sitting (p<0.008). Reaction-time tests had a relatively weak impact on walking-time. Poorer dual-task walking-time responses correlated with slower walking velocity and weaker muscle strength (p< or =.062). Findings suggest that walking requires significant cognitive resources among older adults and slower-walking adults and weaker adults may require higher cognitive loading while walking.