This is probably a stupid question but I’ll ask anyway:
Why is it that when I exercise, I seem to sweat far more on my head and chest (and upper back), then any other part of my body?
Sweat doesn’t always come from the same glands for the same reasons. Going strictly from a (potentially faulty) memory, nervous sweat comes primarily from the armpits, while heat sweat comes from the areas of the body that have the greatest concentration of heat… that is, the head and upper torso. The brain gets a huge chunk of the blood supply from the circulation, and the heart and lungs, during excercise, have to do extra work… which produces extra heat, which causes extra sweating.