Team sports throw me back to nightmare phys ed classes, where I'm the last weakling standing on the line, waiting to be picked for the kickball game, a popularity contest none of us (except the jocks) really wanted to enter. The competitiveness and aggressiveness that so often permeates team sports fuels my insecurities. My fitness activities have always been more metered and solitary. Hiking, yoga and occasional dance classes have been my go-to.

A couple of years ago, when my teen started playing Ultimate Frisbee in a high school league, I was surprised by how much I loved watching the action. Ultimate Frisbee is like a cross between basketball and soccer, only with a "flat ball" that can't touch the ground. The goal is to score by moving the disk from one end zone to another. While the game itself is exciting and fun to watch, it's the mixed-gender play and the camaraderie, even across team lines, that drew me in. Ultimate prides itself on its mixed-gender roots and self-regulated fair play (dubbed the "spirit of the game"). Players and organizers noted my enthusiasm and suggested that I join the summer adult league, which I promptly laughed off.

Even with my reservations about sports, though, I had a secret desire to play. But what if I joined and I couldn't understand the plays? What if I couldn't keep up? I'm 40 (cough, something) and not a runner, and for sure not a sprinter. What if I dropped dead right on the field?

Now, my teen plays in both high school and adult leagues. Unsure about how he'd feel about his nerd mom running around the field embarrassing him, I'd occasionally say something about it and gauge his reaction, which was mostly just a poker face. One afternoon, as we tossed the disc together in the backyard, he said, "You can throw, Mom. You can throw better than some people on my team. Just try it!"

Well, the deadline came and I happened to be sipping a glass of wine when they offered me one last piece of bait: half off the registration fee. In a fleeting moment of overconfidence, I signed up.

Like all things you're secretly scared of, Week 1 came around before I was ready. My kid and I were on different teams, so we arrived together and then walked off to different fields. As I approached my team, I didn't see a single recognizable face. Is there a level higher than threat level red? Because the social-awkwardness needle was encroaching on whatever that was.

As I sat calculating how many laps each of these 20-somethings could run around me, a captain called everyone in and began with an overview of the game. Then the drills began. Ever since an elementary basketball clinic, drills conjure up all kinds of nerves. The universe must have heard my internal plea for mercy and the drills ceased after the first week.

When the game began, it was full-on immersion and I tried to run like I was 20-something too. Except then I couldn't catch my breath and my knees were like, "Hey, hi, what the hell are you doing?" I realized I'd better pace myself and chill. I left that night feeling sore and scared of what my body would feel like the next day.

Over the weeks I began to better understand my body's limits and how I could push it. (It was further than I thought, and that felt amazing.) I felt stronger and more capable than I had in years. The soreness went from the WTH variety to the "Good job, you worked hard and you should feel great about it" variety.

The most interesting weeks were the ones when my team played my kid's team. He was 15, and so we were often angry at each other for a variety of reasons by the time an evening game rolled around -- maybe I'd taken his phone that week, or he had yelled at me on the way there, or I was unreasonably "extra" for insisting he take a lunch to his summer job. We'd glare at each other from opposite ends of the field and play extra hard, though I still couldn't help feeling proud when he'd make a good play or score a goal.

My teen practices all the time. When no one is available to throw the disc with him, he'll throw by himself, perfecting his lesser-used throws, like the hammer, then walk over, pick it up and throw again. Sometimes my 6-year-old will see him out the back window, run out and ask to join him. I imagine this is a mixed blessing -- it's nice to have someone to fetch the disc, but it can be a lot of work to teach a small child how to catch a hurtling disc without being afraid, and how to throw it back with accuracy. One day, I looked out and saw my littlest lunge and throw a perfect flick -- at 6! The next time the three of us threw together, I heard my oldest's active coaching and felt amazed at how the Frisbee has become a conduit for connection in our family.

As the summer season-ending tournament day approached, I was scared. On that day, all of the teams in the league play over the course of about eight hours until two teams are left standing for the finals. We'd play between three and five games, and I knew there was no way I had the stamina for that. My teammates reassured me. "Don't worry, play as much or as little as you can. Don't play hard in the early game -- it doesn't matter. We got you."

We ended up losing after the second game (thankfully). We shouted a team cheer about how the other team creamed us and how awesome they were, played a for-fun consolation game, cracked open some beers and sat down to cheer on my kid in the finals.

A year later, contemplating the approaching summer league again, I ask my kid, while tossing the disc in the backyard, "Hey, do you think it would be cool if I asked to be bagged with you this year?" He shrugs his shoulders, considers the friends he can't then claim for his team, and says, "Sure."