Locomotor Adaptability Task Promotes Intense and Task-Appropriate Output From the Paretic Leg During Walking

Abstract

ObjectiveTo test the hypothesis that participants with stroke will exhibit appropriate increase in muscle activation of the paretic leg when taking a long step with the nonparetic leg compared to during steady-state walking, with a consequent increase in biomechanical output and symmetry during the stance phase of the modified gait cycle. DesignSingle-session observational study. SettingClinical research center in an outpatient hospital setting. ParticipantsAdults with chronic poststroke hemiparesis (N=15). InterventionsParticipants walked on an instrumented treadmill while kinetic, kinematic, and electromyogram data were recorded. Participants performed steady-state walking and a separate trial of the long-step adaptability task in which they were instructed to intermittently take a longer step with the nonparetic leg. Main Outcome MeasuresForward progression, propulsive force, and neuromuscular activation during walking. ResultsParticipants performed the adaptability task successfully and demonstrated greater neuromuscular activation in appropriate paretic leg muscles, particularly increased activity in paretic plantarflexor muscles. Propulsion and forward progression by the paretic leg were also increased. ConclusionsThese findings support the assertion that the nonparetic long-step task may be effective for use in poststroke locomotor rehabilitation to engage the paretic leg and promote recovery of walking.