[Show abstract][Hide abstract] ABSTRACT: To investigate voluntary step behavior of chronic stroke survivors during single- and dual-task conditions and compare the results to healthy age- and sex-matched controls.
Chronic stroke survivors (n=16) and healthy controls (n=16).
Forward and backward rapid voluntary stepping were performed as a reaction time task under 2 conditions: (1) awaiting a cutaneous cue (single task), and (2) awaiting a cutaneous cue while performing an attention-demanding task. Step initiation, preparatory and swing phases, foot-off time, and foot-contact time were extracted from center of pressure and ground reaction forceplate data.
Chronic stroke survivors were significantly slower than healthy controls in all step parameters under single- and dual-task conditions. For dual compared with single task, the foot-contact time increased from 1295 ms to 1445 ms (12%) in chronic stroke survivors and from 876 ms to 1006 ms (15%) in controls.
The significant increase in step phase's duration during single- and dual-task conditions may be a factor contributing to the large number of falls seen in stroke patients. The interference effects of attention-demanding task were similar between groups, suggesting that both groups used similar strategies. Future research should determine whether step training can improve step decrements in chronic stroke survivors.
Full-text · Article · Jul 2009 · Archives of physical medicine and rehabilitation