More than 50,000 runners are expected to take part in the New York City Marathon this Sunday. Some of them will be elite runners chasing glory; the rest will be looking for a personal record or a Boston Marathon qualifying time, or just looking to finish. I won't be doing the marathon this year, but I will be there to cheer the runners on, cowbell in hand. And while I take in this remarkable spectacle, I will also be looking forward to my next race — and reflecting on how grateful I am to have found a sport like this.

For much of my life, sports held little appeal. I spent my time in high school editing newspaper columns and conjugating Latin verbs. The only running I did was when we were forced to slog around our bright blue track for a mile to complete the Presidential Fitness Test.

But next April, I will join about 20 percent of my 1994 classmates and run a half-marathon in Nashville to raise money for our school’s scholarship fund. We’ve started a Facebook group to support one another during our training. We share photos of the scenery we encounter on our runs — for one friend in Georgia, that’s hay bales and the occasional snake; for me, it’s the urban greenery of Prospect Park in Brooklyn — and encourage each other through injuries and raccoon sightings.

I started running 10 years ago, in my 30s, after years of exercise fits and starts — cardio kickboxing! Tae Bo! Dance ’n’ Sweat! — and struggles with eating disorders. I needed to find a workout I could do consistently, anytime, without paying a membership fee . Only one problem: I didn’t know how to run. I’d done it only with a physical education teacher holding a stopwatch and calling me “grandma.”