Editor's Note: Welcome to Day 12 of Guideposts' 14-Day Fitness Challenge! We're sharing stories that will inspire you to eat better and get in shape so you can feel your best. Today's challenge is to fit your passion into your workout. If you're just joining us, check out our previous challenges here.

The theme song from the movie Rocky blasted from the sound system. “Gonna Fly Now”? Yeah, right. I’d never been more earthbound in my life.

I was sprawled facedown in the center-field dirt at Citi Field, the home of the New York Mets, where professional baseball players slugged home runs and made SportsCenter Top 10 catches. Where amateur athletes were strutting their stuff for the day in the Spartan Sprint, a popular obstacle race. I’d signed up for the race, but that must have been in a fit of insanity. Or stupidity.

I didn’t belong here. I was 47 and overweight, despite how hard I’d been working to get in shape. I wasn’t an athlete. I never had been, not since a childhood bout of encephalitis left me with impaired coordination. I was the tallest and gawkiest girl in my grade, the last to be picked in gym class, and teased by other kids.

Maybe God didn’t make me athletic, but he did make me good at one thing involving sports—being a fan. Growing up 10 miles from New York City, I became a die-hard Yankees fan.

My love for the pinstripes didn’t fade with adulthood. I launched and wrote Subway Squawkers, a Yankees-Mets blog, with my friend Jon Lewin, a fan of the Queens team. It probably wasn’t a coincidence that he wasn’t an athlete either. I guess those who can, compete; those who can’t, blog.

As our blog grew in popularity, my physical condition declined. My doctor diagnosed chronic bronchitis and told me that my lifestyle had to change. So I quit smoking. But you don’t kick a 20-year habit without picking up something else. For me, it was food. Potato chips, Big Macs, Twizzlers.

READ MORE: FAITH MADE HIM FIT FOR LIFE

With that diet and spending most days sitting at a computer—besides blogging, I was a proofreader and copy editor at an ad agency—no wonder I put on weight.

Still, I was shocked to see the number on my scale reach 252. That was way too heavy, even for my six-foot frame. I was sick of being fat, of being so out of shape that climbing the subway stairs winded me. Maybe God didn’t make me athletic, but he didn’t make me an unhealthy mess, either. That was my own doing.

If I wanted to get healthy and fit, that would take my own doing too. I worked up my nerve and joined a gym. I also joined Staten Island Slim Down, a weight-loss support group. The other members were like me—middle-aged, overweight, unathletic—so I didn’t feel so self-conscious. Actually, seeing the others doing their best to live healthily inspired me. I even started jogging with the Staten Island Athletic Club.

One day the blog got an e-mail from someone at the Spartan Race company. He asked if we would promote the upcoming Spartan Sprint (one of their shorter races) at Citi Field, figuring our Mets fan readers would be into competing at the ballpark where their favorite team played. He offered us one free entry into the race.

I clicked the link in the e-mail to find out more. The Spartan Sprint would be just over three miles, with more than 15 obstacles set up around the ballpark. The course was “designed to help you discover your inner Spartan.” I showed Jon the web page.

“Wouldn’t it be cool to run around parts of the ballpark where fans normally never get to go, like the dugout and the outfield?” I said. I didn’t say what else I was thinking. Wouldn’t it be even cooler to accomplish something athletic?

“Not my cup of tea,” Jon said. “But why don’t you do it? I’ll go and root for you.”

Was this my chance to be a competitor, not just a fan? I threw aside my misgivings and registered for the race. I had 10 weeks to get ready. I got up early to work out. Did more cardio. Weights. Push-ups. Crunches.

But when Jon and I arrived at Citi Field for the Spartan Sprint, I feared I’d made a big mistake. Participants ran the course in waves. Some were running up the stadium steps carrying sandbags. Others were throwing spears farther than I could throw a pencil.

All of them were hard-bodied twenty-somethings. They actually looked like Spartans from the movie 300. Like grown-up versions of the kids who used to tease me in gym class.

I took a step back, right into Jon. “Sorry,” I muttered. “I was crazy to think I could do this.”

“Lisa, you’ve been training hard,” he said. “No one’s saying you need to win this race, but you owe it to yourself to try.” Jon was right. If I didn’t try, I’d never know what I was capable of. Except quitting.

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The race started with me crawling on my hands and knees up a ramp without dislodging the bungee cords that were stretched over it. I moved on to jumping with a weighted rope. Hopping up stairs with a giant rubber band around my calves. Then came the spear throw—which I failed miserably at, as did most of the participants in my wave.

I did better with the Hercules Hoist—pulling a massive weight on a pulley. Some of the obstacles were fun, like running in the Mets’ dugout. Others, not so much. Like doing 20 hand-release push-ups in the visitors’ locker room. That gave me some nasty carpet burns.

Jon cheered me on. He got to see me toss a medicine ball—a breeze, thanks to those early-morning workouts. He also saw me fall off the monkey bars.

Finally I got to center field and the last three obstacles. A rope climb, a climb over multiple walls, and a cargonet climb. Why did they all have to be climbs? I’d never been able to get halfway up the rope in gym class, even with the teacher’s help. No way could I do these climbs on my own. It’s okay, I tried to console myself. You finished most of the race.

I dropped my head in defeat. One of the race trainers noticed. He reminded me that if I couldn’t do an obstacle, I had another option—do 30 burpees. A burpee? Sounds innocuous, right? Wrong.

A burpee is like a push-up on steroids. You squat, kick your legs out behind you, do a push-up, bring your legs back to the squat position, then jump straight up in the air. The Spartan taskmaster—I mean, trainer—insisted on proper form. It was torture to do a single burpee, and I had to do 30...for each obstacle remaining. That meant a total of 90 burpees!

But it was the only chance I had of finishing the race. Of not being a quitter. I squatted, kicked my legs out. By the fifth burpee, my arms were shaking. On the sixth, they gave way.

That’s how I ended up doing a face-plant in the center-field dirt, “Gonna Fly Now” blaring in the background, taunting me. Then I felt a familiar presence. God was with me, telling me above the music, C’mon, Lisa, you’ve got this!

I picked myself up out of the dirt and went back to burpees. I couldn’t do two in a row without a break. But eventually I completed all 90. With proper form. “Good job,” the trainer said, clapping.

I crossed the finish line with a zip in my step. A race staffer put my Spartan Sprint finisher’s medal around my neck. I burst into tears. I cried so hard Jon thought I’d hurt myself. But they were tears of joy and accomplishment.

Maybe God didn’t make me athletic, but he made me capable. Of getting fit. Of finishing the race. Of loving sports as more than a fan. Those who can, compete. And those who can write, blog about it. Just call me Spartan.

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