Fortune: Why we run until it hurts

They say the best humor comes from pain, so maybe that's why the people I run with are all so hilarious.

An unruly pack of us is just back from the St. Jude half-marathon in Nashville last week. It was a steep, hot, crowded course, and we all finished exhausted and over the times we had targeted. But all I can think of to tell people when they ask me how it went is, "It was so much fun."

This race, like a lot of them, raised gobs of money for a terrific cause. So the world is a slightly better place because we all ran. But seriously, we could just write a check. Instead, we all run because we like to run. Run and run and run.

We train for months, and we laugh and whine, and we cheer each other on, and we sing badly to entertain each other, and we point out all the funny signs we see people holding along the race route (Worst parade ever! Toenails are for losers! Chuck Norris runs from YOU!). And when we're done, we collapse in a sweaty pile and make some mimosas and say, "Ugh, I'm so tired. I inhaled a bug during mile 9. My knees hurt. Let's do another one!"

In the days before this race, my friends and I talked about the case of nerves we always get before a big run -- the kind of nerves that turn your guts into quivering, crampy knots of oh-my-gah-WHERE-is-the-bathroom? And I said, "I think it's because we know we are going to suffer."

And we will absolutely suffer. It's just a matter of how much. On a good run day, you suffer only moderately. On a bad run day, you suffer like a pacifist forced to watch a Three Stooges movie. But there will be suffering, and knowing you are going to suffer is tough on the nervous system.

But the suffering is usually more than justified by the rewards of the run: The super-groovy rush that starts around mile 5; the feeling of (admittedly meaningless) accomplishment in knowing I just ran the distance of my daily commute into work from the 'burbs; the intense camaraderie of these borderline deranged people who all love the same ridiculous things; our gratitude to the useful, remarkable machines that are our bodies.

I think liking to run as much as we like to run also somehow is linked to that slippery, primordial lizard-brain part of our mental makeup that we cannot control at all -- the part that makes you do things that make no sense for deeply concealed reasons driven by millions of years of evolution.

I mean, why do this? We don't have to run to catch food. And we don't have to run to escape predators. We don't even have to run to get from place to place. But we run anyway. And in some part of our collective lizard brains, as we run into mile 11 and IGNORE that searing cramp (because if you ignore it, maybe it will just go away), we are thinking, "If I ever had to catch a buffalo to eat, I could totally run it down, and that schlub drinking a Coke on the curb over there would just have to boil weeds for dinner."

And another part of our lizard brains is thinking, "Yeah, and if a dragon ever attacked our village, I could totally run away from it without stopping FOR HOURS, and those people over there would be painfully, gruesomely seared to death while I disappeared over the horizon, a dust plume blooming from my fleet feet. SUCKERS."

Yes, I know dragons are not real and that I will probably never have to chase down a buffalo. But our lizard brains do not know that. And our lizard brains are always more than ready to justify for us all the illogical things we do. Lizard brains are helpful that way.

Lizard brains also really appreciate juvenile humor. My favorite roadside sign from last week's race: You trained for this longer than Kim Kardashian was married.

Y'all, that's just painfully funny.

Email Mary Fortune at mkfortune@comcast.net.

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