The Procedure of Thermoregulation
The procedure by which the body regulates and continues its temperature is done through a procedure known as thermoregulation. The process entails the maintenance of temperature within positive limits even when the surrounding temperature is dissimilar. As such, the body usually continues a temperature ranging from 36.5 to 37.5 degrees Celsius. The human body additionally produces heat when at rest to hold the body temperature through the strength production of cells with around sixty percentage of it being in the form of heat. The thermo-neutral state of a physique when it is neither spending nor producing heat is affected when the ambient temperature is over 28 degrees Celsius. A higher ambient temperature correction occurs through body cooling mechanisms of heat exchange (Anatomy and Physiology, 2017).
Body Heat Production during Exercise
Body heat production rises during exercise due to the sudden contraction of the human skeletal muscle, high at the onset and plateaus off in constant training (González-Alonso, 2012).
Regulation of Body Temperature during Exercise
One mechanism that the integumentary system uses in regulating body temperature during exercise or physical exercises is through the action of the sympathetic nervous system. It does this through the initiation of motor responses thus when there is a rise in body temperature, the sympathetic nervous system stimulates the sweat gland to produce sweat, and the body is cooled as the sweat evaporates. Second is through the dilation of the arterioles in the dermis which result in excess heat in the blood being dissipated through the skin to the outer environment (Anatomy and Physiology, 2017). The procedure as outlined in figure one occurs as the ambient temperature rises, the peripheral receptors of the hypothalamus are initiated making the vessels close to the skin to vasodilation and heat loss occurs through conduction, radiation, and convection. Over a certain threshold, the central receptors initiate the sympathetic nervous system to start the sweating process (Kuht, J., & Farmery, 2014).
Impact of Core Temperature on Heart Rate
Core temperature is a determining factor in heart rate and as seen in a situation where the heat loss mechanisms of evaporation, radiation, conduction, and convection are not sufficient to maintain body temperature. As such, the core temperature of the body eventually increases when exercise is done in hot conditions thus increasing the heartbeat rate (Achten & Jeukendrup). The increase in heart rate is caused by the redistribution central blood volume to the periphery which reduces the heart's stroke volume. As such, imbalance in cardiac output is corrected through, the heart pumping harder and faster (Galloway & Maughan, 1997).
References
- Achten, J., & Jeukendrup, A. E. (2003). Heart rate monitoring. Sports medicine, 33(7), 517-538.
- Kuht, J., & Farmery, A. D. (2014). Body temperature and its regulation. Anaesthesia & Intensive Care Medicine, 15(6), 273-278.
- Galloway, S. D., & Maughan, R. J. (1997). Effects of ambient temperature on the capacity to perform prolonged cycle exercise in man. Medicine and science in sports and exercise, 29(9), 1240-1249.
- González-Alonso, J. (2012). Human thermoregulation and the cardiovascular system. Experimental physiology, 97(3), 340-346.
- Openstax, Anatomy and Physiology (2017)
