Air-Conditioned Cooling During Consecutive Work-Rest Cycles in the Heat

Assess body temperature changes during three, 45-minute work cycles in the heat followed by 15 minutes of rest in an air-conditioned environment.

Ten participants completed two work-rest trials consisting of three cycles (180 minutes) of 45 minutes walking in the heat (36°C, 40% RH) followed by 15 minutes passive rest (following National Institute for Occupational Safety and Health guidelines). Rest was completed in the hot environment (hot cooling) or in an air-conditioned space (cold cooling). Rectal core temperature (T re ), mean skin temperature, and mean body temperature were recorded throughout work and rest cycles.

No difference in peak T re was observed between hot cooling versus cold cooling conditions at the end of three work-rest cycles.

Passive rest in an air-conditioned space did not mitigate peak T re across three, 60-minute work-rest cycles.