RATING OF PERCEIVED EXERTION AND BLOOD LACTATE CONCENTRATION DURING SUBMAXIMAL RUNNING

We examined whether the relation between of ratings of perceived exert ion (RPE) and exercise intensities associated with the lactate thresho ld (LT) and blood lactate concentrations (BLC) of 2.5 and 4.0 mM, esta blished with an incremental protocol, held during 30-min treadmill run at constant velocity (V). RPE (11.6, 14.9, 16.8, 18.9), oxygen uptake (VO2) (3.2, 3.7, 3.9, 4.2 l.min(-1)), and V (168, 196, 215, 227 m.min (-1)) at LT, BLC of 2.5, and 4.0 mM and peak were determined for nine males during incremental exercise. Subjects then completed three 30-mi n runs at the V associated with LT and BLC of 2.5 and 4.0 mM, with RPE , VO2, and blood [HLa] determined every 5 min. After min 10 during the 30-min runs, RPE, VO2, and BLC were not significantly different from corresponding values observed during the incremental protocol. Regress ion equations predicting BLC from RPE were generated from results obta ined during the incremental protocol. RPE values from the 30-min runs were used to predict BLC, and the measured BLC was used to validate th e use of RPE as a predictor of BLC. Correlations ranged from r = 0.79 to r = 0.98 [total error (TE) ranged from 0.6-1.3 mM]. We conclude tha t RPE is a physiologically valid tool for prescribing exercise intensi ty when the intent is to use LT and/or BLC as the intensity criterion.