Predictors of Improved Aerobic Capacity in Individuals With Chronic Stroke Participating in Cycling Interventions

Abstract

ObjectiveTo determine demographic and physiological factors that predict improvement in aerobic capacity among individuals with chronic stroke participating in cycling interventions. DesignSecondary analysis of data from 2 randomized clinical trials. SettingResearch laboratory. ParticipantsIndividuals with chronic stroke (N=44). InterventionsParticipants were randomized to one of the following interventions: forced aerobic exercise and upper extremity repetitive task practice (FE+UERTP, n=16), voluntary aerobic exercise and upper extremity repetitive task practice (VE+UERTP, n=15), or a nonaerobic control group (control, n=13). All interventions were time-matched and occurred 3 times per week for 8 weeks. Main Outcome MeasureAerobic capacity as measured by peak oxygen consumption per unit time (VO2peak) during maximal cardiopulmonary exercise stress testing. ResultsSignificant improvements in VO2peak were observed from baseline to postintervention in the VE+UERTP group (P<.001). Considerable variability was observed among participants relating to postintervention change in VO2peak. Among aerobic exercise participants, a multivariate regression analysis revealed that cycling cadence, baseline VO2peak, and group allocation were significant predictors of change in VO2peak. ConclusionsHigh exercise rate (cycling cadence) appears to be an important variable in improving aerobic capacity and should be considered when prescribing aerobic exercise for individuals with chronic stroke. Those with low VO2peak at baseline may benefit the most from aerobic interventions as it relates to cardiorespiratory fitness. Further investigation is warranted to understand the precise role of other exercise and demographic variables in the prescription of aerobic exercise for this population and their effects on secondary stroke prevention and mortality.