Effects of maximal speed locomotor training on spatiotemporal gait changes in individuals with chronic stroke: A secondary analysis of a randomized controlled trial.

BACKGROUND

During post-stroke locomotor rehabilitation, repeated fast walking practice improves walking capacity and gait biomechanics. Faster training speed appears to be a key mediator of these effects, but it remains untested whether training at maximal speeds could lead to even more pronounced biomechanical adaptations.

OBJECTIVES

This secondary analysis investigated longitudinal changes in spatiotemporal gait parameters after maximal versus moderate-speed locomotor training in chronic stroke, comparing short-burst high-intensity interval training (HIIT) versus moderate-intensity aerobic training (MAT). Compared to MAT, short-burst HIIT was hypothesized to exhibit greater improvement in non-paretic step length.

METHODS

The HIT-Stroke Trial randomized 55 participants with chronic stroke to short-burst HIIT (N = 27) or MAT (N = 28) for 45-minutes of walking practice, 3-times weekly, over 12-weeks. This secondary analysis compared mean spatiotemporal gait changes between groups, averaging 4-week, 8-week, and 12-week estimates minus baseline. The primary measure of interest was non-paretic step length.

RESULTS

Non-paretic step length increased significantly more with HIIT (+4.4 cm [95 % CI, 1.9, 6.9]) compared to MAT (+0.1 [-2.5, 2.7]; HIIT vs. MAT p = .01). Both groups demonstrated significant increases in cadence and bilateral single support time, and decreases in the coefficient of variation (CV) for stride velocity, time, and length. Changes in step length symmetry were only apparent when assessing individuals with baseline asymmetry.

CONCLUSIONS

Greater increases in non-paretic step length with short-burst HIIT suggest maximal speed training may yield greater increases in paretic propulsion, a marker of walking efficiency. Both MAT and HIIT appear to reduce spatiotemporal variability, possibly indicating improved gait stability.