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

ObjectiveTo investigate longitudinal changes in spatiotemporal gait parameters after maximal versus moderate speed locomotor training in chronic stroke, by 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. DesignSecondary analysis from the HIT-Stroke randomized controlled trial SettingThree rehabilitation research centers ParticipantsIndividuals with chronic stroke and residual walking limitations (N=55) InterventionsParticipants were randomized to short-burst HIIT (N=27) or MAT (N=28) for 45 minutes of walking practice, 3 times weekly, over 12 weeks. HIIT involved 30-second bursts of maximum walking speed, targeting >60% heart rate reserve (HRR). MAT involved continuous walking, targeting 40%-60% HRR. Main Outcome Measure(s)Mean spatiotemporal gait parameter changes between groups, averaging the 4-week, 8-week, and 12-week estimates minus baseline. The primary measure of interest was non-paretic step length, an indicator of paretic propulsion and biomechanical efficiency. ResultsNon-paretic step length increased significantly more in the HIIT group (+4.4 cm [95% CI, 1.9, 6.9]) compared to the MAT group (+0.1 [-2.5, 2.7]; HIIT vs. MAT p = .01). Both groups demonstrated significant increases in cadence, paretic step length, and bilateral single support time, and significant decreases in the coefficient of variation (CV) for stride velocity, stride time, and stride length. Symmetry measures did not significantly change in either group. ConclusionsGreater increases in non-paretic step length with short-burst HIIT suggest that maximal speed training may yield greater increases in paretic propulsion, a marker of biomechanical efficiency. Both moderate and maximal speed training (MAT and HIIT) appear to reduce spatiotemporal variability, possibly indicating improved gait stability.