摘要：We examined whether blowing hot air above body temperature under work clothing may suppress core temperature. Nine Japanese men engaged in two 30-min bicycle ergometer sessions at a workload of 40% VO
2max at 40 °C and 50% relative humidity. The experiment was conducted without wearing any cooling apparatus (CON), wearing a cooling vest that circulated 10.0 °C water (VEST), and wearing a fan-attached jacket that transferred ambient air underneath the jacket at a rate of 30 L/s (FAN). The VEST and FAN conditions suppressed the increases of rectal temperature (CON, VEST, FAN; 38.01 ± 0.19 °C, 37.72 ± 0.12 °C (
p = 0.0076), 37.54 ± 0.19 °C (
p = 0.0023), respectively), esophageal temperature (38.22 ± 0.30 °C, 37.55 ± 0.18 °C (
p = 0.0039), 37.54 ± 0.21 °C (
p = 0.0039), respectively), and heart rate (157.3 ± 9.8 bpm, 136.9 ± 8.9 bpm, (
p = 0.0042), 137.5 ± 6.5 bpm (
p = 0.0023), respectively). Two conditions also reduced the estimated amount of sweating and improved various subjective evaluations. Even in the 40 °C and 50% relative humidity environment, we may recommend wearing a fan-attached jacket because the heat dissipation through evaporation exceeded the heat convection from the hot ambient air.
