Comparing Rate Of Perceived Exertion At Different Levels Of Fatigue In Collegiate Cycling Athletes

INTRODUCTION: Rating of perceived exertion (RPE) is widely used for assessing physical effort and prescribing exercise due to its strong correlation with physiological markers of exertion. PURPOSE: Compare the self-reported power output at two pre-determined RPE levels before and right after a cardiopulmonary exercise test (CPET) with the one reported during the CPET in trained cyclists. METHODS: Seven cyclists from a varsity cycling team (age 19.9 ± 1.6 yr). Each participant attended one lab visit in which they completed a warmup, a CPET, and a cool down. The warmup included a 10-min, self-regulated exercise, followed by a perceptual fatigue assessment consisting of a 5-minute effort during which athletes produced perceived power outputs corresponding to RPE levels of 5 and 7. The CPET was performed on a Monark LC7 cycle ergometer with participants beginning at a power output equal to 50% of their self-reported functional threshold power and progressing by 25 watts every 90 sec. During the CPET, cardiopulmonary parameters (Quark CPET), blood lactate (Lactate Plus), and RPE (BORG CR-10) were measured. The cool-down consisted of a 5-min, self-regulated exercise, followed by the perceptual fatigue assessment. Differences in mean power output during warmup, CPET, and cool down at RPE 5 and 7 were assessed with a paired samples t-test. RESULTS: All athletes achieved maximal effort (oxygen consumption 58.47 ± 7.56 ml/kg/min, RPE 9.71 ± 0.49, respiratory exchange ratio 1.13 ± 0.08, Lactate 9.8 ± 3.06 mMol/L). The power output at RPE of 5 measured during the CPET was higher than the one reported during warm-up (239.4 ± 49.0 vs. 216.4 ± 42.8, p < 0.01) and cool-down (239.4 ± 49.0 vs. 217.9 ± 40.1, p = 0.02). No significant differences were observed between the power outputs at RPE of 5 between warm-up and cool-down. The power output at RPE of 5 measured during the CPET was higher than the one reported during warm-up (285.7 ± 57.5 vs. 273.6 ± 45.7, p = 0.03) and cool down (285.7 ± 57.5 vs. 273.6 ± 37.7, p = 0.08). No significant differences were observed between the power outputs at RPE of 7 between warm-up and cool down. CONCLUSION: These findings suggest trained cyclists can consistently evaluate perceived exertion in a single exercise bout, regardless of fatigue.