RPE drift during cycling in 18 degrees C vs 30 degrees C wet bulb globe temperature.
OBJECTIVE
The potential influence of a hotter vs cooler environment on ratings of perceived exertion (RPE) estimations during longer duration exercise is not well-understood. This study compared overall and differentiated RPEs during cycling in 18 degrees C vs 30 degrees C wet bulb globe temperature (WBGT).


METHODS
Male volunteers (n=16) completed a maximal cycling trial (60 rev . min(-1), 25 Watts . min(-1)) to determine VO(2) max and ventilatory threshold (VT) before completing 2 (counterbalanced) longer duration cycling trials. At 30 degrees C WBGT (30C) and 18 degrees C WBGT (18C), subjects cycled 60 min (60 rev . min(-1), 90% individualized VT). Heart rate (HR, b . min(-1)) and rectal temperature (Tre, degrees C) were recorded every 5 min with corresponding RPE-overall (RPE-O), RPE-legs (RPE-L) and RPE-chest (RPE-C) estimations.


RESULTS
HR was not significantly different at 5 min but was greater (P<0.05) for 30C at all other time points. During 30C, Tre was significantly greater (25, 30, 35, 40, 45, 50, 55 and 60 min), RPE-O was significantly greater (5, 40, 45, 50, 55 and 60 min), RPE-L was significantly greater (55 and 60 min) and RPE-C was significantly greater (35, 40, 45, 50, 55 and 60 min).


CONCLUSIONS
Greater cardiovascular (HR) and thermal (Tre) strain partially explain greater perceptual ratings during 30C. Discernible RPE differences resulted mid-way through 60 min cycling with minimal differences initially. Results suggest RPEs are magnified in a 30 degrees C (vs 18 degrees C) environment beyond 30 min duration. Additionally, a 30 degrees C environment resulted in a less pronounced impact on RPE-L (vs RPE-C and RPE-O).
Green
J M
JM
Department of Kinesiology, The University of Alabama, Tuscaloosa, AL 35487, USA. mgreen@bamaed.ua.edu
Pritchett
R C
RC
Crews
T R
TR
Tucker
D C
DC
McLester
J R
JR
Wickwire
P J
PJ
D000328:Adult; D000704:Analysis of Variance; D001642:Bicycling / Q000502:physiology; D001833:Body Temperature Regulation / Q000502:physiology; D005080:Exercise Test; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology; D005082:Physical Exertion / Q000502:physiology*; D013696:Temperature