Physiological index
sweat loss
Rectal temperature (HR was measured using a wireless HR monitor (RS800CX, Polar Electro, Finland) at 1-min intervals. The towel-dried nude body mass was measured using a scale (InBody 470, InBody Japan, Japan) before and after the experimental trial. Gross sweat loss was estimated by adjusting for fluid intake. The urine-specific gravity was measured using a refractometer (PAL-09S, Atago, Japan) before and after the experimental trial.