Oh my god, this is foul.
If you're exercising so hard that you shit yourself, then you're exercising too hard. Human bodies weren't made for such intense exercise. We were made to roam over long distances to hunt and gather. Roam, not run as fast as possible. That's why top athletes have such trouble with their bodies for the rest of their lives. There was a marathon runner on my office, and even though he had the body type for it - very tall and thin - he still needed a hip replacement at 40.
Exercising so hard that you shit yourself is utterly ridiculous.