Figure 3. Heart rate (A,B), rating of perceived exertion (C,D) and thermal comfort (E,F) during 30 min of continuous submaximal cycling exercise (SMT) at approximately 60% VO2peak in hot conditions before (pre) and after (post) 5 sessions of high intensity interval training (HIIT) in the heat (Acc; temperature = 38.7 ± 0.5 °C, relative humidity = 34.4 ± 1.3 % or Con: 22.3 ± 0.2 °C; 35.8 ± 0.6 %). Values are mean ± SD, n = 7 per group except for heart rate where n = 6 for Con. Main effect for training, ^p < 0.05. Difference between pre and post training at all corresponding time points within the Acc group, * p < 0.05. Mean rating of thermal comfort during pre is different from post training within both Acc and Con groups, # P <0.05. Acc: acclimation, Con: control, HIIT denotes high intensity interval training.