The core body temperature is monitored by the hypothalamus, and is a form of negative feedback which maintains the internal environment at 37C despite the heat of the external environment. This is a form of homeostasis, and it is essential as low temperatures will slow down metabolic reactions, whereas on the other hand high temperatures will cause the denaturing of enzymes and proteins. The body responds to the increase in heat by vasodilation of arterioles supplying blood to the skin, therefore increase heat is lost by radiation. Also sweat glands release more sweat, and the high latent heat of evaporation means heat will be absorbed as it leaves the surface.
However players would have to loose approximately 1.5-2.5 litres of water an hour from their bodies in 43C, although as the maximum someone could drink in that time scale is 1litre, there will be a deficit. This leads to heat exhaustion due to loss of fluid and salts and can result in players feeling light headed, nauseous and muscle cramping. In these conditions the players are also at serious risk of heatstroke, this is when the body can no longer control its body temperature and begins to overheat. Heatstroke is more likely to occur in athletes such as tennis players because there bodies don't slow down as body temperature increases. It usually occurs after fainting, heat exhaustion or heat cramps and is considered a medical emergency as it can cause death or serious brain injury.
Muscle cramps and cooling of the body is best treated by applying ice packs to places such as the armpits and the groin, as this helps cool the body down and increase blood flow into muscles.
References:
http://en.wikipedia.org/wiki/Thermoregulation
http://www.bbc.co.uk/news/health-25758278
http://www.webmd.com/a-to-z-guides/heat-stroke-symptoms-and-treatment
No comments:
Post a Comment