Single Limb Exercise: Pilot Study of Physiological and Functional Responses to Forced Use of the Hemiparetic Lower Extremity

Purpose: Stroke-related deficits can impede both functional performance and walking tolerance. Individuals with hemiparesis rely on the stronger limb during exercise and functional tasks. The single limb exercise (SLE) intervention was a unique training protocol that focused only on the hemiparetic limb. Our objective was to determine the effect of the SLE intervention on cardiorespiratory fitness parameters. Methods: Twelve participants (5 male) with a mean age of 60.6 +/- 14.5 years and 69.1 +/- 82.2 months post stroke participated in the training intervention. All participants performed SLE using the hemiparetic leg three times a week for 4 weeks. The nonhemiparetic limb served as the control limb and did not engage in SLE. Peak oxygen uptake (VO2 peak) and oxygen uptake (VO2) were measured at baseline and post intervention in all 12 participants. At pre and post intervention, gait velocity was assessed in a subset of participants (n=7) using the 10-m fast-walk test. Results: After the 4-week SLE training intervention, significant improvements were found for VO2 during submaximal work effort (P=.009) and gait velocity (n=7) (P=.001). Peak oxygen uptake did not increase (P=.41) after the training intervention. Conclusion: These data suggest that SLE training was an effective method for improving oxygen uptake and reducing energy expenditure during submaximal effort. Unilateral exercise focused on the hemiparetic leg may be an effective intervention strategy to consider for stroke rehabilitation.