During strenuous exercise there are several factors in our bodies that tend to change. These changes that occur cannot stay that way they need to be returned back to a normal state. This is why our bodies have homeostatic mechanisms operating all the time, to return our bodies back to a constant internal environment. This constant internal environment needs to be maintained in order to carry out both basic and complex functions. One factor that is influenced by prolonged strenuous exercise is the change in body temperature. A core temperature of approximately 37 degrees Celsius is needed because the chemical reactions that occur in the body are very heat sensitive. There is a thermoregulatory centre located in the hypothalamus that balances the heat losses and the heat produced.
During exercise there is a tendency that the body temperature of the person exercising to increase. This is due to the increased activity of the cells and muscles and also an increased breathing rate. The responses that occur during this exercise to maintain this constant internal environment are shown in a negative feedback loop. These are used to show the process from where the body first encounters an increased body temperature, then all the steps in between and then finally what the body does to counteract and keep the body temperature regulated. The stimulus, the change that can be detected by the body is the increased body temperature. The receptor is the organ that detects this change, and in this case are the brain, the thermo receptors in the blood vessels, peripheral thermoreceptors in the skin that provide the information on the external environment and the central thermoreceptors in the medulla. These heat receptors are receptors where there is an increase in temperature. The modulators are what notes the changes and determines the response that is needed. The modulator here is the brain and in it the hypothalamus.