Regulating intensity using perceived exertion in spinal cord-injured participants

Purpose: To examine the validity of perception-based intensity regulation during handcycling exercise. Methods: Eight spinal cord-injured (T11 incomplete to T4 complete) participants completed an incremental exercise test followed by a V·O2peak test using a sports hand bike. Subsequently, two 20-min exercise tests were completed at an individualized power output (PO) at moderate and vigorous intensities (50% and 70% of V·O2peak, respectively). On a separate occasion, participants were instructed to produce and maintain a workload equivalent to the average RPE for the 20-min imposed condition in a counterbalanced order. The V·O2 and blood lactate concentration [BLa-] were measured every 10 min, and HR and PO were measured at 1-min intervals. Results: There were no differences in average V·O2, percent V·O2peak, HR, PO, and [BLa-] between the imposed PO conditions and RPE-regulated trials of either exercise intensity. Although PO increased slightly during the moderate-intensity RPE-regulated trial (P < 0.04), it remained relatively constant in the vigorous RPE-regulated trial. However, there was a tendency for PO to be slightly higher (P = 0.07) in the vigorous RPE-regulated trial. Conclusions: These data suggest that RPE is effective in controlling moderate and vigorous intensities throughout a 20-min handcycling exercise session for SCI participants.