Maintaining a good, steady and stable core temperature is important for an athlete. Without this, many knock-on effects will take place and thus impede on their performance. However there are a few factors that will cause the body’s temperature to fluctuate. For example; the environment, the climate, the duration of exercise, type of exercise, intensity of the exercise and if there are rest periods/ the duration of them. Depending on these factors, core temperature will adapt, and then use different strategies in order to combat the unwanted extra heat or gain some heat back.
Heat loss strategies:
Hypothalamus- a group of specialised neurons that regulate the body’s temperature (to around 37C). These cells get a greater supply of blood in order to function better. The ways it regulates temperature is: the skin has thermal receptors which receive information about any temperature changes, and then sends messages to the hypothalamus.
The hypothalamus detects the changes in temperature directly through the constant supply of blood it gets. Methods:
1) Conduction- works through contact with other objects for the transfer of heat. Rate depends on the temperature difference between you and the object (quicker the air moves around the body, the quicker the heat will dissipate). For example: when sitting on a cool bench outside for 10 minutes, then when you stand up and touch the bench, it will feel warm.
2) Sweating- cools the body through evaporation… sweat is secreted by the body and placed on the skin’s surface, through this, evaporation can take place to cool the person:
Sweat glands secrete saline solution (NaCl dissolved in water) = sweat
Cooling process only happens when the sweat evaporates from the skin’s surface… air surrounding the body becomes saturated with the sweat that’s been evaporated… so when new air comes in, it can accept the new evaporated sweat.
But on a dry and hot day, the limiting factor for evaporation would be rate of sweat production. This is because the nature of the hot day, significantly increases the amount of sweat produced, therefore it can’t all evaporate at a fast enough rate.
3) (main method for heat loss) Throughout day to day life and exercise, heat is radiated towards cooler objects through electromagnetic waves, for example: walls, trees, buildings or the ground. (the closer the objects are, the less heat will be lost. Also depends on the person too… if they have a high proportion of fat then they will retain their hat and so lose heat at a slower rate compared to a slimmer person- this is because of their body composition and mass)
4) a combination of evaporation (from the moisture in the lungs) and convection (the displacement of warm air in the lungs, by cold air from the surrounding environment coming in). Moisture is lost through exchanging the air in the lungs with drier air from outside the body. This occurs during breathing.
5) the movement of molecules across the body results in heat being taken off and away from the body because of the convective currents passing by. For example, wind cools you down through increasing the flow of air that passes over the skin, which then carries the heat from the body away with it.
The limiting factors for how effective and efficient these methods are at cooling the body are: age, gender, race and the training they undergo.
Effects of high temperature:
High temperatures in hot and humid environments can cause our normal methods of heat loss to become unproductive, which can then lead to hyperthermia. This occurs due to the hypothalamus being compromised, meaning the body temperature isn’t managed and kept at 37C, instead it’s allowed to rise to 40C+.
Initial effects= emotions or how you feel:
Loss in concentration
Less capable to do