Exercise Physiology Flashcards
4 Ways in which heat loss can occur
conduction, convection, radiation + evaporation.
Conduction
heat exchanged by two objects in contact.
Convection
heat exchanged by contact with fluid that is flowing.
Radiation
occurs when heat is transferred from a warmer body to the cooler surroundings without physical contact.
heat loss = occurs when core temp is higher than ambient temp
heat gain = occurs when ambient temp is higher than core temp
Evaporation
the cooling of the body as a result of the vaporisation of sweat. (most effective in dry conditions)
Dehydration
occurs when the amount of water leaving the body is greater than the amount being taken in.
Heat acclimatisation
when heat tolerance is improved by repeated exposure to hot environments.
Exercising in cold weather
athletes will use more glycogen and fats due to shivering using them as a fuel source. this will have a negative impact on performance as glycogen stores will deplete earlier in the event.
- increase amount of CHO and fats in diet.
Physiological response to cold weather
peripheral vasoconstriction, shivering, piloerection
Peripheral vasoconstriction
involves the redirection of blood flow, away from the skins surface and towards the bodies core, to help minimise heat transfer from the blood to the cold external environment.
Shivering
involuntary muscular contractions designed to help increase heat production.
Piloerection
when the hairs on the body stand on end and trap a warm layer of air close to the skin to help keep the skin surface warm.