Thermoregulation and Fluid Balance

Thermoregulation is how the body holds its core temperature close to 37°C by balancing heat production against heat loss, with the hypothalamus acting as the thermostat.

Exercise generates a large heat load, and losing it depends heavily on sweating, which ties temperature control closely to fluid and electrolyte balance. In hot or humid conditions the body can struggle to keep up, and both too much heat and too much fluid can be dangerous.

For sport and exercise medicine (SEM) this matters most at events and pitchside, in recognising and preventing heat illness and exercise-associated hyponatraemia.