Sweating is one of the body’s primary mechanisms for cooling down. When the body’s internal temperature rises, sweat glands produce moisture that evaporates from the skin’s surface, releasing heat and hence cooling the body.
Conversely, shivering is the body’s mechanism for generating heat when the internal temperature drops. Shivering is a reflexive response that causes muscles to contract rapidly, generating heat to raise the body’s temperature.
Vasodilation, dilation, and constriction of blood vessels can also impact body temperature. For example, blood vessels near the skin’s surface dilate when the body needs to cool down, allowing more blood to flow through them. This increase in blood flow helps to release heat from the body. On the other hand, when the body needs to conserve heat, blood vessels near the skin’s surface constrict, reducing blood flow and conserving heat.
All of these mechanisms play a role as you get ready for bed and ease into the different stages of sleep. You may have experienced this shift in temperature before. For example, whenever you feel cold in bed and putting socks on makes you feel a bit warmer, that’s because a lot of heat loss occurs through our extremities — hands and feet. Thus, covering them will help make you feel warmer. Conversely, when you feel warm under the covers but don’t want to fully kick off the blanket, sticking your feet out from under the blanket may be the heat relief you need to be able to fall asleep.
