Why Does my dad say its good to wear a jumper while running?

Question

I run everyday in the morning. And he says " wear a jumper, because then u sweat and ur cloths asobes it."

" because its bad when ur skin opens up to release the sweat, and cold air enters."

True or not?

Answer 1

sweating is your body trying to cool itself, if you cover up, you prevent your body from cooling and it overheats- thats bad