This lady openly discussed with the NY Post her decision to poop herself at mile 13.1 of a marathon in order to stay on target for a PR. She finished the race and cleaned up at the medical tent.
I can understand accidentally doing it and cleaning off in a porta potty during the race. I can understand if $$$$$ is on the line during the Olympics or a major (even than I don't know if I'd want to risk poop running down my legs on worldwide television). But doing it and running another 13.1 miles in soiled shorts just to hit a PR with nothing else on the line?