Table 1.

Rating of perceived exertion, ventilatory and cardiovascular responses during prolonged submaximal exercise with and without hyperthermia

	Time (min)	RPE	V̇O2 (l min−1)	V̇CO2 (l min−1)	PET,CO2 (mmHg)	PET,O2 (mmHg)	Systolic BP (mm Hg)	Diastolic BP (mmHg)
Control trial	10	10 ± 1	2.63 ± 0.12	2.41 ± 0.11	44.8 ± 0.9	98.7 ± 1.0	163 ± 2	66 ± 3
	20	11 ± 1	2.63 ± 0.11	2.38 ± 0.11	44.6 ± 0.9	98.9 ± 1.1	164 ± 2	65 ± 2
	30	12 ± 1	2.64 ± 0.11	2.37 ± 0.10	44.2 ± 0.9	98.5 ± 0.9	164 ± 2	64 ± 2
	40	12 ± 1	2.63 ± 0.13	2.35 ± 0.11	43.6 ± 0.9	98.8 ± 0.9	164 ± 2	63 ± 2
	50	12 ± 1	2.61 ± 0.12	2.38 ± 0.11	43.7 ± 1.0	98.5 ± 1.4	165 ± 2	63 ± 2
	60	12 ± 1	2.61 ± 0.11	2.34 ± 0.10	43.2 ± 0.8	99.1 ± 0.8	165 ± 2	63 ± 2
Hyperthermic trial	10	13 ± 1	2.56 ± 0.11	2.34 ± 0.10	44.9 ± 0.8	97.2 ± 1.7	162 ± 3	66 ± 2
	20	14 ± 1	2.59 ± 0.10	2.39 ± 0.10	43.4 ± 0.7*	99.9 ± 1.5	159 ± 2	64 ± 2
	30	16 ± 1	2.60 ± 0.11	2.40 ± 0.10	41.0 ± 1.1*†	101.7 ± 1.4*†	159 ± 3	60 ± 2*†
	53 ± 4	20 ± 0	2.63 ± 0.10	2.51 ± 0.11*†	38.6 ± 0.6*†	105.3 ± 1.5*†	156 ± 3*†	57 ± 2*†

Values are means ±s.e.m. for 8 subjects. RPE, rating of perceived exertion; P_ET,CO2, end-tidal CO2 pressure; P_ET,O2, end-tidal O₂ pressure. The final point in the hyperthermic trial (53 ± 4min) is the average time to exhaustion (range 37–59 min).

^*Significantly different from 10 min value, P < 0.05;

^†significantly different from control, P < 0.05.