I was at mile 10 of my 10th half marathon, the D.C. Rock ’n’ Roll Half Marathon on Saturday, which was also the third anniversary of my first-ever half marathon, when my 59-year-old brain went to the place it always goes when I feel like I’m done.

Gonna die.

This is different from hitting the wall, or bonking, which is what happens when your body runs out of glycogen, or carbohydrate stores, your body’s main source of energy, and you become hopelessly, tragically fatigued.

I didn’t bonk.

There wasn’t any chance of my bonking.

I had spaghetti and meatballs the night before Saturday’s race, and I topped off my glycogen on the morning of the race with a cinnamon raisin bagel smeared with peanut butter, half a grapefruit, and a banana. By mile 10 I had consumed from the genius pockets of my Lululemon running pants and from the baskets of spectators and race volunteers dates, pretzels, Swedish Fish, Sport Beans, Glukos Energy Gummies, Rolos, and Hershey’s kisses. And Gatorade at the water stops.

I passed up the cups of Guinness set up on a card table by a group of hipsters on Bryant Street but that’s only because there was a mini Reese’s Peanut Butter Cup in my mouth. It’s a race after all so it didn’t seem appropriate to stand there and stop and chew and then grab a cup.

No, what I was feeling at mile 10 was that I wanted to stop. Not that I needed to stop.

It was like there was plenty of fuel in the tank but the engine kept cutting out.

Then I remembered two things, 1. what my physical therapist Kevin McGuinness told me when I was rehabbing an injury at least three injuries ago, “you’ve done this before,” and 2. a study I read when I first started running by Samuele Marcora, an exercise physiologist at the University of Kent, UK, who concluded fatigue is all in your head.

The study, originally published in 2008, measured the cardiovascular and muscular systems of subjects, half who cycled to exhaustion after conducting a taxing cognitive activity and half who did not. The mentally fatigued subjects hit the brakes earlier than the control group, and the scientists were able to show that the subjects with the tired brains perceived exertion even though their muscles had plenty more oomph.

As a newer, not very good runner, I’m interested in this idea as well as other scientific theories about why we are naturally programmed to stop exercising before we actually need to. Some say it’s our built-in survival instinct, to stop doing something before it kills us. Others, including sports and performance psychologist Chris Friesen, author of Achieve, point out that our brains are especially gifted at sending us negative thoughts, telling us to stay inside when it’s cold or to walk or quit 10 minutes into a run or a race.

And so there’s a whole body of research and an entire profession of coaches and sports psychologists and yogis dedicated to helping athletes and even the rest of us train our brains along with our bodies to connect the two.

I PR’d on Saturday with a finish of 2:56:18. And that’s without a pit stop, which is a first for me. To put that in perspective, that’s about an hour longer than most of the #instarunners posting their results Saturday afternoon.

Yet at mile 10, when I wanted to quit, I looked at the runners around me. And behind me. All ages, all shapes, all outfits, all pushing through discomfort. I used the opportunity to tell my brain that what I was feeling would not last forever. I learned this trick from meditation guru Sharon Salzberg one weekend at Kripalu.

And then just as I finished my internal body scan, a suggestion from yogi Sarajean Rudman, looking for what was feeling good so I could focus my brain on that and settling on my awesome left shoulder, it dawned on me.

Three years ago, I wanted to quit at mile six. But right then a good friend turned up standing by the side of the street drinking her morning coffee and telling me I got this. I wanted to tell her everything hurt, but I persevered, rounded the corner, and, miraculously, I finished.

Wow, three years later, I’ve improved four miles.

Ha.

As a back-of-the-pack runner, it’s never about my performance even if it’s performance psychology that’s providing me with as much energy as the caffeinated GU in my pockets. What gets me to the start, and ultimately across the finish, is knowing that there is hardly a greater sense of satisfaction or even joy or thrill than living through the experience of persevering.

And then of course there’s lunch.

Originally published at medium.com