Studies have reported that ratings of perceived exertion (RPE) are a valid tool for
exercise prescription when blood lactate concentration (BLC) is used as the intensity
criterion. However, few have studied the relationship between RPE and BLC during commonly
used graded exercise tests (GXTs) and simulated exercise training. The purpose of
this study was to determine if the RPE: BLC relationship is transferable across GXTs
and a steady state exercise trial (SST). Thirteen healthy males (25±5.3 yrs) completed
two maximal treadmill tests (Bruce and Balke protocols) followed by a SST which consisted
of - 8 minutes of exercise at each of two intensities (~ 40 % and 70 % maximal heart
rate reserve). BLCs and other physiollogical measures were compared at matched RPEs
across the GXTs and SST trial at each exercise intensity using a two-way repeated
measures ANOVA. There were no significant differences in BLC at a matched RPE across
the exercise trials at the lower exercise intensity with the BLCs being 1.5±0.3, 1.6±0.6
and 1.3±0.3 mM, respectively. However, at the higher exercise intensity BLCs were
significantly lower during the Balke GXT compared to the Bruce GXT and SST (1.8±0.6,
2.8±1.8 and 3.0±0.8 mM, p < 0.05). These results suggest that the RPE: BLC relationship
may be protocol dependent during graded exercise testing as it was only transferable
from the Bruce GXT to the exercise training setting at intensities in the typical
prescription range of 50 - 85 % of VO2max.
Key words
RPE - exercise prescription - exercise training intensity - graded exercise testing
- estimation model
