what is it called when your body tempture goes up really fast in cold weather?

Question

what is it called when your body warms up in tempture really fast in cold weather and then you get a feeling like needles constanly pooking you mostly in the back and it happens usallsy during tennis practice?

Answer 1

Its called a fever...a fever is your body trying to fight a virus

and if its during physical activity its the release of endorphins from your brain into your blood stream