I've noticed in my high number of excessive years of the sport that normal people who have these kinds of mental problems (schizo or severe bipolar/tri or tetrapolar) tend to get religion, and runners who have them tend to get ultras.
Fact. Most religious people are not mental cases. But mental cases are drawn by religion because it does have a lot of insane ideas built in.
Same with ultras. Most ultrarunners are danged nice, and mostly sane. But runners who crazy (schzioaffective in my family's case) go right to ultras when they can. Lots of fertile stuff there, self induced suffering and endorphins up the weeezooo and lots of weird strange unshowered stinky folks.