it's still plenty cold out there! Ever wonder why we shiver like Jell-O when we are cold?
Shivering is like a dance that your body does to keep warm. Everyone has a built-in thermostat in his or her body called a HYPOTHALAMUS. Your hypothalamus is in your brain, and it makes sure that your body is at about 98.6 degrees AT ALL TIMES. If you get colder than that, your brain starts to tell your muscles to warm up by moving around.
Movement - like playing sports or having a snowball fight - requires energy. When you jump around, your muscles break down food to get energy and this process releases heat in your whole body. If you stop moving and your body gets chilly, your muscles will move all by themselves to keep you warm - and that's what we call shivering!