Fig. 4
Motor adaptation: Spatiotemporal and metabolic adaptation during the first exposure to split-belt walking. We quantified motor adaptation by measuring the extent of spatiotemporal adaptation from the first five strides (‘initial’) to the final twenty strides (‘late’) of the first exposure to split-belt walking (‘Adapt 1’). Additionally, we assessed the magnitude of metabolic adaptation by comparing the second minute (‘early’) of Adapt 1 to the last minute (‘late’). (A) We observed substantial reductions in step length asymmetry during Adapt 1, indicating spatial motor adaptation. (B) In contrast, step time asymmetry remained high without significant changes. (C) Double support time asymmetry significantly decreased from initial Adapt 1 to late Adapt 1, consistent with temporal motor adaptation. (D) Net metabolic power significantly reduced during Adapt 1, suggesting improved metabolic efficiency. The circles and light grey lines depict individual data. The bars represent standard error. Significance levels are denoted as ***p < 0.001, **p < 0.01, and *p < 0.05.
