RPE Drift in Fit and Unfit Males Cycling in a Hot and Cool Environment

The potential influence of aerobic fitness on RPE estimations during extended exercise bouts is not well understood. The current study compared RPE-Overall, RPE-Legs and RPE-Chest between fit (n=7) and unfit (n=6) males. Subjects completed a graded cycling test and then, in a counterbalanced order, on two separate days cycled for 60min (intensity~90% of the Onset of Blood Lactate Accumulation (OBLA) - determined via gas exchange indices) at 30}1 degrees Wet Bulb Globe Temperature (WBGT) and 18}1 degrees WBGT. Heart rate (HR), rectal temperature (Tree) and overall and differentiated RPE estimations were collected every 5 minutes. Repeated measures analyses of variance showed no significant differences (p\u3e0.05) between groups for RPE-O, RPE-L, RPE-C. There were no significant differences between groups across time for HR or Tree. Similarly, there was no significance between - group differences for core temperature increase (Tree at 60min – Tree at 0 min) or absolute HR drift (HR at 60min- HR at 5min) within cool or hot cycling trials. This suggests fit and unfit males experienced similar relative cardiovascular and thermal strain. Results indicate that, between fit and unfit males cycling at similar individualized relative intensities, overall and differentiated RPE estimations are not influenced by aerobic fitness level during 60 minutes of exercise in 18 or 30 degrees WBGT