Abstract
Background We previously found that increasing propulsion demands during split-belt walking (i.e., legs moving at different speeds) facilitates locomotor adaptation. There is a clinical interest to determine if this is also the case in stroke survivors.
Objective We investigated the effect of propulsion forces on locomotor adaptation during and after split-belt walking in the asymmetric motor system post-stroke.
Methods To test this, 12 chronic stroke subjects experienced a split-belt protocol in a flat and incline session so as to contrast the effects of two different propulsion demands. Step length asymmetry and propulsion forces were used to compare the motor behavior between the two sessions because these are clinically relevant measures that are altered by split-belt walking.
Results The incline session resulted in more adaptation (i.e., less limping) during late split-belt walking and larger after-effects following split-belt walking. In both testing sessions, stroke subjects adapted to regain speed and slope-specific leg orientations similarly to younger adults. These leg orientations achieved during split-belt walking were predictive of the post-adaptation behavior.
Conclusion These results indicated that the asymmetric motor system post-stroke can adapt to meet leg-specific kinetic demands. This promising finding suggests that augmenting propulsion demands during split-belt walking could favor symmetric walking in stroke survivors, perhaps making split-belt interventions a more effective gait rehabilitation strategy.
