Perceptually regulated training does not influence the differentiated RPE response following 16-weeks of aerobic exercise in adults with spinal cord injury

This study investigated the effect of prolonged familiarisation with ratings of perceived exertion (RPE) on the peripheral (RPEP) and central (RPEC) RPE responses to moderate-vigorous exercise in adults with spinal cord injury (SCI). RPEP and RPEC characterize the exertion of the working musculature and cardiorespiratory systems, respectively. Nineteen participants (41.4±11.4 years; 19.2±7.2 ml·kg-1·min-1) with chronic SCI were randomly assigned to RPE-guided (n = 11; EXP) or active control (n = 8; CON) groups. EXP performed 16-weeks of RPE-guided, supervised aerobic training for 20 mins, twice weekly, at RPE 3-6 (Category-Ratio 10 scale). CON had access to the same exercise equipment but received no specific advice on their exercise-training regime. Participants completed a graded exercise test, using an arm crank ergometer, pre- and post-training to determine peak oxygen uptake (V̇O2peak), with RPEP and RPEC recorded every minute throughout tests. Sixteen weeks training did not improve V̇O2peak. RPE decreased post-training at 50% (p = 0.02) and 70% V̇O2peak (p = 0.03), though there was no effect of group at either intensity (p = 0.54, 0.42 respectively). At 70% V̇O2peak RPEP was greater than RPEC (4.2±1.7 vs 3.4±1.8, p < 0.005). Training with RPE-guidance for 16-weeks had no additional effect on the differentiated RPE responses to moderate-vigorous exercise in adults with SCI