How Does the Body Regulate Temperature?
The body has developed its own internal thermometer and feedback system so that if a rise or fall in temperature is detected, the body reacts to return the temperature to normal. For example, if you exercise, the work of your muscles generates heat; the hypothalamus, a gland located deep within the brain, sends a message to blood vessels to dilate and to the sweat glands (to sweat) which help remove heat and cool the body. You may voluntarily remove clothing or choose looser clothing, or, eventually, body temperature will rise so high you will feel too lethargic to continue exercising (not a good sign). Conversely, if you find yourself out in the cold, the blood vessels constrict to conserve body heat, you shiver to generate more heat or you may voluntarily bundle up or head for a warmer place. Sometimes these mechanisms don t work well for example, a condition called poikilothermy is the inability to keep body temperature constant when the environment changes; normal infants (and rare
