Three minutes into my first half marathon, I thought I would lose my mind.

I’d decided to run it with the “2 ½ hours” group, not trusting myself alone to set a steady pace and happy to be among others who, like me, had no loftier goal than finishing alive. Sure, I’d never run in a group before (or even alongside a single other person), but this was an event, with crowds and cowbells and music blasting at the start line, so I was fully prepared for a different kind of running experience from my norm of solitude. What I didn’t anticipate was that the two pacers for the “2 ½ hours” group were planning to carry on a conversation for the full 13.1 miles, loud enough for the whole pack to hear and join in.

I was frantic.

So I did exactly what you’re not supposed to do. I took off, madly zigzagging to get ahead of the crowd (“Sorry!” “Sorry!”) until I reached a relatively isolated spot beyond hearing range and, shooting regular glances over my shoulder, held my lead for the rest of the race, finishing not only alive, but at a better time than I’d ever, in my wildest dreams, imagined.

When you’re an introvert, the need for quiet is a powerful motivator.

Until that race, I hadn’t realized just how much my running — the physical act of running — depends on my being able to think, how much I rely on quiet for energy. The best runs (that is, the easiest) are those in which I’m so deep in thought — revising a bit of writing, weighing the pros and cons of a difficult decision — the uphills barely register, the miles disappear. I’m fortunate to live in a rural area in northern Vermont where I can usually run in solitude, where the noise of traffic and interactions with others are rare. When there is another person on the route who shouts something at me — Hey! How’s it going? — the disruption can be jolting, pulling me out of my reverie but not quite into full consciousness.

Running, for me, is not a social activity. It is an extremely private affair.

It has taken me a while to admit this. When I began running, what I found nearly as debilitating as the onslaught of pain was the sense that I was doing something against my nature, something I wasn’t supposed — maybe not even allowed — to do. I was 61 when I started nearly five years ago, with decades’ worth of entrenched notions of who I was — and wasn’t — to contend with. I’m a hiker, an outdoorsy person, but being outdoorsy is not the same as being a runner. Runners are athletes: outgoing, competitive souls who thrive in groups, love events, gain energy from running among hordes, cheer, high-five, and wear bright, logo-screaming gear. This was not me — quiet, non-sporty, non-groupy me. I knew this. Everyone who knew me knew this.