Reason #7: "Yeah, there's a little sadomasochism there..."
This is one of my favorite jokes:
"Running is easy. Everyone can do it."
It may not seem funny to you right now, granted, but trust me, when you're struggling to maintain an 8:30 pace over a long run after playing ice hockey the night before, it's basically the funniest joke ever.
The fact is that running isn't easy. Not even when you've been doing it for a while and you'd consider yourself pretty good at it. Sometimes running hurts; other times it just plain sucks.
Part of running is a certain capacity to give and accept a certain amount of physical punishment in order to attain a goal. Otherwise, no one would ever do track workouts and there would be no such thing as a tempo run or a hill workout.
And I think sometimes that this part is the point for me.
I'm human and I live in society; I therefore have concerns. I do things wrong and there are things about myself that I can't fix. And running is a really, really effective outlet for my frustrations. When I fuck up, or say the wrong thing, as I inevitably do, I can't take it back, and the way my brain works means I can't let it go, so maybe that day I run a little harder, push it a little farther.
I'm aware that maybe this isn't healthy, as a mindset, but at least running is a healthy activity. The capacity - maybe the need - for self-flagellation is there, and running is an effective means of letting it out to play.
I don't hate myself and I don't feel the need to intentionally harm myself, but sometimes I think that maybe if I didn't have running, I wouldn't be able to say that.