Validity of Rating of Perceived Exertion Ranges in Individuals in the Subacute Stage of Stroke Recovery

Background: Rating of perceived exertion (RPE) is used to monitor or prescribe workload of exercise, but its utility among individuals with a stroke remains in question. Objective: To examine the validity of RPE at multiple percentages of peak aerobic capacity (VO2peak) in individuals in the subacute stage of stroke recovery. Methods: Thirty-seven patients with stroke in the subacute stage of recovery from an inpatient rehabilitation institute completed a graded Maximal exercise test on a semi-recumbent cycle ergometer. Respiratory gas exchange was monitored for analysis of VO2, while heart rate and RPE (Borg CR10 Scale) were measured at the end of each minute. RPE was compared with expected ranges when at 60%, 70%, and 80% of VO2peak. Post hoc analyses were performed to determine whether patient characteristics differed between participants who fell within and outside the expected RPE range at 80% of VO2peak. Results: Median (interquartile range) RPE at 60%, 70%, and 80% VO2peak. were 3.0 (3.0-3.5), 3.0 (3.0-5.0), and 4.75 (3.0-5.75), respectively; 76.2%, 69.0%, and 38.9% of participants fell into the expected RPE range at each intensity. Patient characteristics were similar between participants who fell within and outside the expected RPE range at 80% VO2peak. Conclusion: RPE appears to be a reasonable indicator of exercise intensity after stroke at moderate (60%-70% VO2peak) but not high-intensity exercise (80% VO2peak). This conclusion is based on the high degree of between-subject variability in RPE at 80% VO2peak. Future research should identify whether RPE can be adapted to accurately capture exertion during high-intensity exercise after stroke.