Every evening at eight o’clock, a middle-aged woman who reminds me of myself hobbles past my house. She wears black leggings and reflective sweats, her hair drawn into a ponytail that jerks sideways as she hurls herself forward. This mystery woman leaves her car down the block while putting mileage, instead, on her body. When I first moved to this low-traffic neighborhood six years ago, she jogged up the brightly lit center of the road with brisk, purposeful strides. Then she began to favor one ankle and gravitated toward the curb. Elbows sharp, hips swiveling, she switched to race-walking. Over time, her form progressively deteriorated, but she never missed a single night. Now, she contorts her knees and torso, her gait crablike and her pace just ahead of a crawl. The only thing about this woman that doesn’t match my past self is her preternaturally blond hair.

Though I’m often in front of my house when my alter ego passes, she does not look up—at me or at anyone. Her face and posture make it clear that she is as intent on her bodily pain as the most devout self-flagellant. Yet if I were to demand why she chooses to subject herself to such punishment, I doubt religion would be her excuse. Instead, from behind the same mask of defensive superiority that I used to wear, she would tell me she does it for her health.

Fitness, beauty, energy, health: how well I know those self-righteous excuses! For the sake of my “looks” I dropped thirty pounds at the start of adolescence and held my weight below one hundred (the picture that comes to mind now is that of a child holding a terrified cat underwater) until my last year of college. In the name of “nutrition” I refused to eat meat from age fourteen to thirty-five, when my consequent lethargy finally bordered on black-out. To “shape up” as a teenager I would go for four-hour bike rides, during which I refused to downshift even when climbing forty-degree hills. Pain, to my thinking, meant gain. The more my body hurt, the more my willpower gloated. A war was underway, my physical constitution its battleground. Health was no more my real goal than cheap tea was the object of the American Revolution. The celebrants at the Boston Tea Party, however, enjoyed one advantage over masochists like the eight o’clock jogger and me: they understood that they were fighting a war of independence.

We exercise zealots instead believed that ours was a higher cause. The logic that guided us was the same that, over the centuries, has justified foot binding, corsets, plastic surgery, and hair shirts—a logic that equates perfection with unnatural suffering. Far from fighting an oppressive king, we voluntarily reduced and mortified ourselves in the name of the current king of culture: fitness. Maybe, we thought, if we ran just a few more miles a day, or worked off another hundred calories on the Stairmaster, or spent another half hour at the gym, we’d finally stop worrying about not looking or acting or being good enough. Then, at last, we’d feel free—without having to rebel against anyone except our physical selves.

ESSAY CONTINUED in FOR KEEPS