Here's why you stick your feet out from the covers in bed at night
Next time you lie down to go to sleep, pay attention to what your feet do. Do you also stretch one foot out from under the covers? I wouldn't be surprised if you did, because this is a brilliant natural method for sleep.
The background: Researchers have determined that wakefulness and body temperature share a close relationship with one another. When we are tired, our body temperature drops dramatically. This signals to our brain that it is time to sleep.
But where do your feet come into the equation? The secret is in the soles. There are two qualities of the soles of your feet that are very important: first, they are hairless, and second, they are home to a specially-structured vein network that helps your body to regulate its temperature. This network is called arteriovenous anastomosis. The veins help regulate the blood flow to your skin, thus making it colder or warmer. Therefore, when a cool, nighttime breeze brushes the soles of your feet, it cools the blood under the skin. This cooler blood then flows through the rest of your body, lowering your body temperature and sending your brain a "sleep" signal.
In contrast, a high body temperature makes us more alert and improves our memories - an important survival mechanism in the past. So, when you are warm, you can do a lot of things better, but sleeping isn't one of them.
That's why so many people, often unconsciously, stick a foot out from under the covers. Next time you have the feeling that you just can't get to sleep, pay attention to where your feet are. Maybe you just need to stretch your toes out for a bit of fresh air.