It’s a habit many people don’t even think about. In the middle of the night, without fully waking up, one leg slowly slips out from under the blanket. For some, it feels more comfortable. For others, it just happens automatically. But there’s actually a scientific reason behind this common sleeping behavior.

The body constantly works to regulate its temperature while you sleep. In order to fall asleep and stay asleep, your internal temperature needs to drop slightly. If you become too warm under the covers, your brain signals your body to release heat — and one of the fastest ways to do that is by exposing a part of your skin to the cooler air.

Your feet play a major role in this process. They contain specialized blood vessels that help release heat quickly. When you stick one foot out of the blanket, it allows excess body heat to escape, helping your temperature stabilize and making it easier for your body to remain in a deep, comfortable sleep.

Sleep experts say this simple cooling effect can actually improve sleep quality. Instead of waking up overheated or restless, the body naturally adjusts its temperature through this small movement. That’s why many people who sleep this way don’t even realize they’re doing it — their body is simply responding to what it needs.

There’s also a psychological comfort factor. For some people, having one leg outside the blanket creates a balance between feeling covered and secure while still allowing freedom of movement. It’s a small adjustment, but it can make a big difference in overall comfort during the night.

So if you’re someone who wakes up with one foot sticking out, there’s no need to worry — it’s actually a natural temperature-control mechanism your body uses to help you sleep better. Sometimes, the little habits we don’t notice are actually signs that our body knows exactly what it’s doing.