This study determined the effects of hypohydration on aerobic performance in compensable [evaporative cooling requirement (Ereq) equal less than maximal evaporative cooling (Emax)] conditions of 10 deg C [7 deg C wet bulb globe temperature (WBGT)] 20 deg C (16 deg C WBGT), 30 deg C (22 deg C WBGT), and 40 deg C (27 deg C WBGT) ambient temperature (Ta). Our hypothesis was that 4% hypohydration would impair aerobic ...