We did not observe any differences in blood lactate among temperature treatments (F3, 160 = 2.33, P = 0.08; Table 3); however, we did note differences in blood lactate over time (F4, 160 = 5.65, P < 0.001). Blood lactate at Tmin throughout the elevated thermal cycles (t = 72–120 h) did not differ from the pre-thermal stress intermediate Tmin (t = 48; P = 0.96 and P = 0.87, respectively), nor was there a significant difference at the peak of the first heat cycle (t = 60 h; P = 0.06). However, blood lactate was significantly higher at the peak of the third heat cycle compared with the initial pre-temperature stress condition prior to thermal ramping (t = 108 h; P = 0.02). Significant decreases in blood lactate were observed at t = 120 h compared with both thermal peaks (t = 60 h and t = 108 h; P = 0.004 and P = 0.001, respectively).