Movement Amplification Training to Enhance Walking Balance Post-Stroke

Project Summary People with chronic stroke (PwCS) have substantial walking balance dysfunctions that limit independence and participation in walking activities. There is a pressing need to develop effective methods to enhance walking balance in PwCS. Interventions that amplify self-generated movements may accelerate motor learning by

enhancing an individual’s perception of movement errors. This method could potentially be applied to help PwCS improve walking balance. To this end, we have developed a cable-driven robot to create a Movement Amplification Environment (MAE) during treadmill walking. The MAE challenges walking balance by applying

lateral forces to the pelvis that are proportional in magnitude to real-time lateral center of mass (COM) velocity. Here we propose to evaluate the effects of gait training in a MAE on walking balance in PwCS. Aim 1 will quantify locomotor adaptations that PwCS make to maintain walking balance in a MAE and evaluate the impact of MAE

strength, a key gait training variable. We will also examine short-term changes in the ability of PwCS to control their lateral COM excursion during walking (a quantifiable walking balance measure) immediately after MAE training. Aim 2 will evaluate long-term changes in walking balance and daily walking following a 5-week high-

intensity gait training intervention performed in a MAE. For Aim 1, we will conduct a single-session cross sectional study wherein twenty PwCS will each participate in two experiments evaluating gait biomechanics (whole body center of mass dynamics and stepping patterns) during and immediately following MAE training. Locomotor

adaptations during walking in a MAE and the effect of MAE strength (low, medium, and high) will be examined. We will measure changes in the ability of PwCS to control their lateral COM excursion during walking immediately before and after walking in a MAE. Outcomes will assess if short-term walking balance is enhanced immediately

following MAE exposure. For Aim 2, we will employ a pre-post study design wherein ten PwCS will participate in 10-sessions of high intensity gait training performed in a MAE. We will assess pre- to post- changes in walking balance using clinical gait and balance measures, biomechanical assessments, and participation in daily walking

(steps/day). Outcomes will assess if long-term walking balance is enhanced following MAE gait training. Our innovative training paradigm, amplifying individuals own self-generated movements, is a radical departure from current practice and could substantially enhance walking balance in PwCS. This study will provide valuable

insights about the mechanisms employed by PwCS to maintain their walking balance in a MAE and if beneficial behaviors persist following MAE training. Successful outcomes will motivate a randomized controlled trial to assess efficacy of MAE training on walking balance in PwCS. The broad aim of our proposal aligns closely with

the mission of NINDS/NIMH Exploratory Neuroscience Research Grant R21 program to support early-stage projects that seek to develop novel methodology to reduce the burden of neurological disease.