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 characterise the exertion of the working musculature and cardiorespiratory systems, respectively. Nineteen participants (age, 41.4 +/- 114 years; peak oxygen uptake, 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 min, 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 at pre- and post-training to determine peak oxygen uptake, with RPEP and RPEC recorded every minute throughout tests. Sixteen weeks training did not improve peak oxygen uptake. RPE decreased post-training at 50% (p = 0.02) and 70% peak oxygen uptake (p = 0.03), though there was no effect of group at either intensity (p = 0.54, 0.42, respectively). At 70% peak oxygen uptake, 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. Novelty In adults with SCI, differentiated RPE responses were not different between those who did, and did not, perform 16 weeks of RPE-guided training. This challenges whether familiarisation with RPE is necessary to be an effective regulator of exercise intensity in this population.