Dual-task walking and automaticity after Stroke: Insights from a secondary analysis and imaging sub-study of a randomised controlled trial.
Collett J., Fleming MK., Meester D., Al-Yahya E., Wade DT., Dennis A., Salvan P., Meaney A., Cockburn J., Dawes J., Johansen-Berg H., Dawes H.
OBJECTIVE: To test the extent to which initial walking speed influences dual-task performance after walking intervention, hypothesising that slow walking speed affects automatic gait control, limiting executive resource availability. DESIGN: A secondary analysis of a trial of dual-task (DT) and single-task (ST) walking interventions comparing those with good (walking speed ⩾0.8 m s-1, n = 21) and limited (walking speed <0.79 m s-1, n = 24) capacity at baseline. SETTING: Community. SUBJECTS: Adults six-months post stroke with walking impairment. INTERVENTIONS: Twenty sessions of 30 minutes treadmill walking over 10 weeks with (DT) or without (ST) cognitive distraction. Good and limited groups were formed regardless of intervention received. MAIN MEASURES: A two-minute walk with (DT) and without (ST) a cognitive distraction assessed walking. fNIRS measured prefrontal cortex activation during treadmill walking with (DT) and without (ST) Stroop and planning tasks and an fMRI sub-study used ankle-dorsiflexion to simulate walking. RESULTS: ST walking improved in both groups (∆baseline: Good = 8.9 ± 13.4 m, limited = 5.3±8.9 m, Group × time = P