Why do you keep shivering when your body is warm?

Answer 1

Not very effectively. Shivering is a last-ditch attempt by the body to generate heat in it's own muscles to try and ward off increasing cold, but the operative words are "last ditch" - it just doesn't help much if one is really chilled.

Answer 2

muscular activities produce heat, shivering is a muscular activity; like exercising so therefore heat is produce to keep you warm.

Answer 3

Shivering when you are warm can mean that you have a temperature - however you would usually 'feel' cold but 'be' warm for this to be the case.