system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does sticking one foot out from under the blankets prevent me from getting too hot?

So you're under the covers... it gets a bit too warm, so you stick your foot out from under the covers and a damn near perfect temperature is achieved.  Why's that?
gpt
When you are warm, blood flows more readily to your hands and feet.  When you are cold, blood flows away from them, making them colder than the rest of your body.  This keeps your core (your torso) more consistent in temperature and protects from overheating or hypothermia (an extreme case of being too cold).

As a result, on a warm night, much of your body's heat might be in your feet, where it can radiate away better to try to cool you down.  In addition, your extremities perspire (sweat, though "only pigs sweat") very readily when hot.  This explains why sticking your foot out can cool you down, just as much as why wearing good gloves and shoes/socks can keep you warm when it is cold.