Increasing Relative Humidity Impacts Low-Intensity Exercise in the Heat

Abstract

Nonevaporative and respiratory heat loss mechanisms failed to offset decreased sweat evaporation. Nonlinear increases in Tre appeared to catalyze responses in most other variables, which demonstrated similar but temporally delayed patterns. Under these circumstances, an RH threshold for increased thermal strain plausibly existed between 55-70RH; environmental characteristics indicated the threshold occurred not where heat stress became uncompensable, but instead where Tre surpassed the "balance point," triggering compensatory responses.