Asymmetric gait training with a Tied-Belt Treadmill

Walking post-stroke is frequently characterized by slower speeds, due in large part to a precipitous decrease in paretic limb push-off [1]. This decrease in push-off, frequently quantified as the peak of the anterior component of the ground-reaction force vector (FP), often requires persons post-stroke frequently rely on compensatory gait strategies such as vaulting and increased push-off from their healthy leg [2]. A critical target for rehabilitation, therapy frequently aims to elicit volitional improvements in paretic limb push-off with unfortunately lackluster results. Therefore, rehabilitation approaches that do not require volitional changes in gait are needed. To address this need, we aim to develop a novel dynamic treadmill training approach. Our dynamic treadmill controller uses changes in tiedbelt treadmill speed to modulate the magnitude of paretic and non-paretic push-off. For example, accelerating the treadmill during paretic push-off should increase the magnitude, as pushoff magnitude scales linearly with walking speed [3]. Similarly, decreasing the speed during non-paretic push-off should decrease compensatory push-off from that limb. Importantly, we can customize the treadmill speeds and timing of the speed changes to shape each individual’s push-off. As such, we hypothesized that walking in our dynamic treadmill would result in greater push-off from the leg moving quickly during push-off than that moving slowing during push-off in young healthy participants. The results will be used to refine treadmill control for persons post-stroke.