Walking Speed Can Be Modulated on an Adaptive Split-Belt Treadmill

Adaptive treadmills (ATMs) that change speed based on the users’ gait mechanics can allow for healthy stride-to-stride variability observed during overground walking while maintaining the benefits of traditional treadmill training for gait rehabilitation. To enable unilateral modifications, the purpose of this study was to develop and validate an adaptive split-belt treadmill (sATM) that updates the speed of each belt of the treadmill based on the user’s propulsion and position to enable preferential targeting of unilateral gait mechanics. Fourteen young, healthy participants completed five trials at their comfortable walking speed on an existing tied-belt adaptive treadmill (ATM) and sATM with unilateral and bilateral modifications. The participants maintained similar propulsion and belt speeds between treadmills and belts for bilateral modifications. As a group, participants showed no change in propulsion and differences in walking speed for the unilateral modification, demonstrating successful enabling of unilateral modifications. Our results suggest that the sATM may require further tuning to encourage unilateral control strategies. The present study provided a proof of concept of a novel treadmill controller that can enable unilateral modifications, performed technical validation by demonstrating equivalence to an existing tied-belt ATM, and explored unilateral propulsion targeting to demonstrate unilateral modifications.