Abstract
We examined the effects of intensity of training on ratings of perceived exertion
(RPE) at the lactate threshold (LT), fixed blood lactate concentrations (FBLC) of
2.0, 2.5 and 4.0 mM and peak in 25 untrained eumenorrheic women (x̄±SD: age = 30.9±4.1
yrs; height = 165.7±5.9 cm; weight = 65.5±7.6 kg) who completed one year of run training.
Subjects were recruited as sedentary controls or were randomly assigned to one of
two training groups: 1) at the lactate threshold (@LT) or 2) above the lactate threshold
(> LT). The @LT group trained at velocity LT and the > LT group trained at the velocity
midway between velocity LT and peak velocity. Training subjects were reevaluated every
fourth menstrual cycle and training intensity was adjusted. The control group was
reassessed at menstrual cycle 12. Before training no among group differences were
observed for V̇O2 or velocity at LT, FBLC and peak. Both training groups increased V̇O2 at LT, FBLC and peak as a result of training (p < 0.05), with the > LT group exhibiting
greater improvement than the @LT group (V̇O2 at LT, FBLC of 2.0, 2.5 and 4.0 mM and peak increased by 6.4, 5.3, 5.1, 4.0 and 4.7
ml/kg · min-1 for@LT and by 10.4, 9.2, 8.6, 5.1 and 5.9 ml/kg · min-1 for > LT; p < 0.05). Similar findings were observed for the velocity associated with
these lactate concentrations. No pre/post differences were observed in V̇O2 or velocity for the control group. In spite of the differential training response,
RPE remained stable at LT and FBLC of 2.0, 2.5 and 4.0 mM and peak (x̄ RPE = 12.3,
14.7, 15.8, 17.6 and 19.3, respectively). We conclude that RPE remains stable at LT,
FBLC and peak independent of changes in fitness or training intensity. Therefore,
if blood lactate concentrations are used for exercise prescription, RPE may provide
a suitable means for regulating training intensity.
Key words
RPE - lactate threshold - fixed blood lactate concentrations - exercise - running
