Sunburn, exercise... then blisters everywhere? Help?

It's just the dead skin (that will eventually peel off) holding the sweat in.

Nothing to worry about.

Should I still keep working out or take it easy?

I see no reason to stop working out because of it. I mean...I work out in the sun, and usually burn pretty badly at the beginning of the summer. I've had this happen in the past...and just kept working. No issues have come of it. The skin would come off on its own anyhow eventually.

I once got a sunburn where I had blisters as a result. It turns out that sunburns are literal burns, so blisters = second degree burns.

I would have them checked out by a dermatologist. I had to have my sunburn treated with burn ointment!

If you didn't aggravate the burn by getting in the sun again, i.e., got a worse sunburn, the blisters are just sweat that ends up trapped under the layer of epidermis that you haven't shed yet from the burn. If you made the sunburn worse, as in you burned it further, blisters are a sign of a second-degree burn, where you burned past the initial layer of epidermis, and although they aren't life-threatening on their own, they sure are painful, and can increase risk of infection if the burn is bad enough or covers a very large area. I actually still have scars on my shoulders from a nearly third-degree burn I got from being out in the sun one day, so they can be pretty serious. That's why I always wear sunscreen now, even for shorter periods, because burns of any kind increase your skin's risk for developing issues later on in life.

From your description, it sounds like you just sweat, and it got stuck. I wouldn't worry about it, because it will go away on it's own, though if you go outside again while it's still burned, cover up. Don't just wear sunscreen, because it will have no effect on dead or damaged skin cells. Literally cover it all up to keep it safe while healing.

I had the same thing happen.I got a terrible burn on a Friday after cardio and weight training on Monday I was just still burnt. Tuesday after an hour of cardio and weight training the blisters appeared. There's no way it is sweat. I continued to heat from a second degree sun burn and on Tuesday it finally blistered. My Dr. is going to let me exercise but nothing in the gym can touch my back because of the extremely high risk of staff infections and other infections in the gym if the blisters were to burst. I also have to use burn cream twice a day. Even though it is a sun burn remember it's still a second degree burn over a large area on your largest body organ. I realize this thread is old but with weather warming I wanted to share the medical advice given to me by my Doctor.