It hurts! And burns. All your spots flare up even more when you run or do a hard workout and you need to shower soon after to wash off the salty sweat. During my really bad months, I avoid running altogether. Instead, I lift weights and keep things calm to avoid sweating. It's also extra important to not have super lenient eating habits if working out is off limits because of your skin. I say all of this as if I would workout and eat healthy every day if I didn't have eczema. Nope. Sometimes having eczema makes me feel like I'd be a gym rat and marathon runner if only I didn't have eczema. But I immediately tell myself, "yeah right!" Either way, I just ran three miles and have to squeeze in a quick workout before my skin screams for a shower!