Table 2. Differences in the thermoregulatory responses between pre-pubertal boys and girls exercising in hot and humid environments. Response Females Males Circulatory Cardiac Output (Q̇) Higher Lower Stroke Volume Lower Higher Heart Rate Higher or similar Lower or similar Skin blood flow ? ? Blood pressure ? ? Changes in blood volume ? ? Temperature Core body temperature (TC) Higher or similar Lower or similar Rate of increase in TC Slower or similar Faster or similar Skin temperature Similar Similar Heat loss (E) Similar Similar Heat loss (R, K & C) ? ? Fluid regulation Sweating rate Lower Higher or similar Sweat electrolyte loss Similar Similar Sweat gland size ? ? Sweat rate per gland Lower Higher Number of HASG Similar Similar Metabolic VO2 Similar Similar Abbreviations: ? = no available research, E = heat loss via evaporation, R, K & C = heat loss via radiation, conduction and convection, HASG = Heat activated sweat glands.