What happens to the body's temperature during sleep?

April 1, 2010

There is a close association between the core temperature of the body and feelings or tiredness or vigor. When the body cools down, one is bound to feel sleepy and fatigued. When the body warms up, we tend to feel alert and full of energy. Not everyone may be aware that the temperature of the human body functions like an internal clock which regulates the sleep cycle. Other functions of the body are also controlled by body temperature. These functions include circulation of blood and metabolism. There are also many other involuntary functions which the body performs under the regulation of body temperature.

It is important to note that the feeling of being wide awake or exhausted depends upon the rise and fall of the body’s temperature. This means that when the temperature of the body drops, one feels drowsy and sluggish. On the other hand, when the temperature of the body increases, one feels attentive and active. However, these fluctuations of body temperature throughout the day should not be mistaken as the need to sleep. Variations in core body temperature take place several times during the day based on the body’s level of activity at a particular point in time. If the body is subjected to heavy physical demands, the temperature will automatically increase above the normal level. In a similar manner, after any vigorous physical activity, the temperature of the body will reduce.

Towards the evenings, the body temperature starts to fall along with adrenalin levels. Adrenalin is one of the hormones involved in wakefulness and alertness. The body may also begin to sweat slightly as it attempts to prevent loss of heat. The temperature will continue to drop as the night progresses and by around 5 o’clock, it would have fallen to approximately 1˚C below what it was in the evening. Along with this, the rate of metabolism also drops and during this time the body feels the most tired. This is on account of the fact that both body temperature and adrenalin levels reach their lowest point. The low body temperature enables much deeper sleep, thereby allowing the body time to rebuild and rejuvenate. Once the body temperature starts increasing, it becomes increasingly difficult to remain in deep sleep. One can also provide rest to the body by taking short naps of 10 to 30 minutes during the day. These naps should not go beyond 30 minutes as then the body will enter deep sleep and the body temperature will drop further

Submitted by M T on April 1, 2010 at 03:39

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