Thermoregulation 5, Body temperature

Normal body temperature varies a little between individuals. Mine is normally about 36.4oC however, up to 37oC is considered normal. Occasionally individuals have temperatures, which are normal for them, of as low as 36oC to as high as 37.5oC. Individuals with persistently high body temperatures are uncommon; the vast majority of times you record a temperature of 37.5oC it will be an indication of an infection or tissue damage. If the environment is very cold then core temperature may start to drop. People are particularly prone to lowering body temperature if they are immobile or wet as well as cold. If the core temperature drops below 35oC this may be described as hypothermia.

During physical exercise body temperature may rise to 38oC and vigorous exercise may elevate this as high as 40oC. However, these rises soon trigger cooling responses from such mechanisms as sweating. Whenever total heat gain exceeds heat loss body temperature will start to rise. This can occur in very hot environments or when cooling mechanisms are unable to function.

Wearing a lot of clothes prevents heat loss to the environment and reduces evaporation of sweat. For example, soldiers have become hyperthermic while exercising in full kit on hot days. Like hypothermia, hyperthermia is a life threatening condition and must be corrected as a matter of urgency.