I have friends who do hard things. One is walking across England. This is a process that will take ten days and a team of baggage bearers, not to mention a few zeros on the old plastic. But this is what he wants to do and even bribed a couple of sons to go too. Another friend is head over heels into working out. She arrives at the gym in clean clothes and a dry brow, and after an hour or so slumps back to her car covered in sweat. She pays for the privilege of doing this. Yet another woman gives good money to be afforded the luxury of running in a marathon. This entails childcare, weeks of training and cash, not to mention physical pain.

Perhaps all of these people have done smaller versions of these obstacles and ended up looking for higher hurdles.

"Twenty pull ups? I'll do thirty."

"Ran five miles? Make it twenty."

No one is forcing these adults to submit themselves to expensive suffering. They chose it. Maybe they can articulate to a lump like me what the bennies are. Maybe not. I notice my involvement is restricted to Facebook updates.

Marriage starts out easy. Most people can keep pace for the first year without quitting. But then the Great Trainer ups the ante and you have to work harder. Instead of being kind when you are both clean and well fed you are expected to remain calm when the car breaks down in a thunderstorm outside of Tulsa and the only food you brought is crackers. Once you master that, there are new challenges, like babies. Try doing pull ups with one of those in a moby wrap.

Perhaps it is hard to explain why people do it. Maybe the words don't even exist. But when I spend time with a couple who have been running side by side for a lifetime, the sweat and tears seem like a small price to pay.