Can the Borg RPE Scale Be Used to Prescribe Resistance Exercise Intensity?

Abstract

0067 Rating of perceived exertion (RPE) scales are widely used to both assess the intensity of aerobic exercise and as a tool to prescribe exercise of an appropriate intensity to improve aerobic fitness. The reliability and validity of RPE scales when applied to resistance type exercise, particularly non-fatiguing contractions, have been less extensively studied. PURPOSE: To determine the internal consistency and interindividual variability of RPE responses to different percentages of a 1 repetition maximum lift (1-RM) for 4 different exercises. METHODS: A 1-RM was determined for subjects (n = 43) performing knee extension (KE), knee flexion (KF), elbow flexion (EF) and shoulder abduction (SA) on Kaiser pneumatic resistance equipment. Subjects returned within 7 to 10 days and provided RPE values using the Borg 15 point scale for lifts requiring 20, 40, 60 and 80% of their 1-RM presented randomly for all 4 exercises. RESULTS: Internal consistency of application of the Borg scale was evaluated by examining the relationship between RPE and %1-RM for each individual for each exercise and then for all 4 exercises combined. Mean r values ranged from .95 (EF&SA) to .98 (KF&KE) for individual exercises with little variability (CV = 2–7%) and averaged .89±.06 for all 4 exercises. Interindividual variability was assessed by determining the variability in both the slopes of the lines describing the relationship between RPE and %1-RM and the averaged RPE response over all 4 %1-RM's for each of the 4 exercises. Average slope values ranged between .12 (EF) and .15 (KF) with moderate variability (20–33%). Average reported RPE's ranged from 10.4 (EF) to 12.4 (KE) with modest variability (12–13%). CONCLUSIONS: The Borg RPE scale was very consistently and linearly applied by each individual within and across muscle groups when performing non- fatiguing lifts. Interindividual variability was greater but similar to that reported when the scale is used to assess aerobic exercise intensity. Taken together, these data suggest that RPE might be useful in predicting %1-RM. Accordingly, a chart predicting %1-RM from RPE provided after performing a nonfatiguing contraction was developed.