Face cooling during hyperthermic exercise significantly reduced prolactin release (175 vs 373 mIU/L; P<0.05) and heart rate, but had a relatively small effect on the perception of effort.
Does face cooling reduce perceived exertion and prolactin release during hyperthermic exercise in non-heat-acclimated males?
Face cooling during hyperthermic exercise significantly reduces prolactin secretion and provides a small reduction in perceived effort.
Absolute Event Rate: 175% vs 373%
p-value: p=< 0.05
The present study investigated whether face cooling reduced both the perceived exertion (RPE) and prolactin (PRL) release during hyperthermic exercise. Ten, non-heat-acclimated males (23 +/- 2 years; maximal oxygen consumption, 56 +/- 7 ml kg(-1) min(-1) mean +/- s.d.) exercised for 40 min on a cycle ergometer at 65% of their peak aerobic power, at an ambient temperature of 33 degrees C (27% relative humidity) with (FC) and without face cooling as a control (CON). With FC, forehead temperature was maintained approximately 6 degrees C lower than CON, while other skin sites were similar or slightly warmer in the FC condition. Rectal temperature increased by approximately 1.5 degrees C with the same time course in both conditions. A relative bradycardia was observed during FC, with heart rate approximately 5 beats min(-1) lower than CON (P < 0.05). Mean plasma lactate was lower during FC (FC, 5.0 +/- 0.3 mmol l(-1); CON, 5.9 +/- 0.3 mmol l(-1); P < 0.05) but no differences were observed for plasma glucose, which remained constant during exercise. Levels of PRL were maintained at 175 +/- 17 mIU l(-1) during exercise for FC, while values for CON increased to a peak of 373 +/- 22 mIU l(-1) so that towards the end of the exercise, for the same rectal temperature, PRL was significantly lower in the FC condition (P < 0.05). Global and breathing RPE were reduced but only towards the end of the 40 min of exercise during FC, whilst subjective thermal comfort was significantly lower during FC (P < 0.05). We confirm the substantial effect that FC has on the secretion of PRL during hyperthermic exercise but show that it makes a relatively small contribution to the perception of effort when compared to the effect of a cool total skin area as occurs with exercise in a thermoneutral environment.
Mündel et al. (2006) studied Hyperthermic exercise (n=10). Face cooling vs. Without face cooling (CON) was evaluated on Prolactin (PRL) release (p=< 0.05). Face cooling during hyperthermic exercise significantly reduced prolactin release (175 vs 373 mIU/L; P<0.05) and heart rate, but had a relatively small effect on the perception of effort.