Small bumps on skin from heat, what could it be?!

Small bumps on skin from heat, what could it be?

so since December every time i've worked out or gotten very hot my skin has formed bumps over almost every part of my body. These bumps are small, not discolored, don't itch, and don't burn. After I've cooled down, the bumps will disappear within' the hour. I've been to a general doctor and then a dermotologist. They both looked confused and have never seen it before, which is not very comforting. I've searched for answers all over the internet and no one seems to have exactly what I have.

Here are some photos:

http://farm1.static.flickr.com/254/52316...

http://farm1.static.flickr.com/218/52317...

3 weeks ago
I'm sure if it were heat rash, the dermatologist would've diagnosed it as that, but I read heat rash gets red, my bumps aren't red, the red spots are just the way my skin looks normally. It has nothing to do with sun because I don't have to be outdoors, I just have to be hot.

Well, if the docs don't know, who does. My grandson was faced with the same thing. I'd watch what kind of detergents and bath soap and shampoo that I use--make sure they are mild and without a lot of fragrance. Do a little shopping. Rub yourself down with corn starch and make sure you bath before going to bed and make sure you launder your sheets and bath towels often. It might be something you have to live with.