Once I realised you could cry in Spin class, it was over.

To take it back a bit, I was not a very fit adult. Like many women, I equated going to the gym with various desperate, full-throttle attempts to become smaller – feverish, week-long periods of daily visits that were abandoned when I failed to immediately drop a stone. To take it back further, I was once a dictionary-definition “indoor kid”, whose lack of athletic ability was exceeded only by my lack of interest in doing anything other than reading under a blanket. As a result, my peers never chose me in gym class, and a classic “not really one for physical activity” complex was born, with no real malice on anyone’s part.

And then I got married, and then last year I got divorced. We don’t need to get into the whys or hows; the situation is that one day I was someone’s wife, and then, after a horrifying 18-month limbo period during which I alienated many friends with too much martini-crying, I was not. I held the documents ending our marriage in my hands and thought how unexpected it was to be somebody’s ex-wife. The follow-up thought came immediately, and fully formed: time to become somebody’s upsettingly fit ex-wife.

If you are interested, for reasons of narcissism or masochism, in experiencing what it’s probably like to be famous, I would venture you can approximate the feeling by getting divorced within a small community (in my case, the small-town-in-big-city-clothing that is Toronto). Everywhere, friends and acquaintances are interested in the minutiae of your new routine, probing for stories to prove you are, actually, moving on, and for any anecdotes that may later make good gossip. People remark on whether you’ve been going to the gym, or going out a lot, or did something new with your hair. Your social media account is trawled for evidence of a bitchy reference to your ex, a renewed commitment to healthy eating, a drinking problem, a tragic secret. Heads swivel if you bring a friend to an event – someone else? Already?

My change of circumstance made me hyperaware of what I wanted everyone to see: a woman in charge of herself. A Strong Woman Doing Well On Her Own. A woman (I’m sorry) thriving. The logic was this: if I looked good I was doing well, in a way that anyone could see before I opened my mouth. I was tired of the gentle arm squeezes and soft-eyed how-you-holding-ups, of people checking in to make sure I was “taking care of myself”. I figured that becoming inarguably, conventionally attractive would cut them off at the pass, giving them a narrative they understood (“glow up” is a universal language) and saving myself the trouble of figuring out what I actually felt. I was comforted by the cut-throat simplicity of it: to be hot was to be doing well. Better than before, better than him. Better than other, weaker people who are broken by something as small as grief. I didn’t pause for a minute to consider how unhealthy it was to look on a breakup as a competition. I just knew that I did not want to be a loser. I wanted to be the winner, and very hot. And so: to Spin.

Spin, for the three people who still don’t know, is where the hot girls live. They thrive there, amid the expensive shampoo, pristine white lockers and sparse changing rooms with nowhere to hide. Occasionally a very hot boy will muscle his way into a class, wearing an article of clothing that was once a T-shirt and is now cut so deeply around the neckline and armpits it’s a sort of reverse-bib, pert pectorals peeping out as if to say, “Later I will put powder in a water bottle, shake it, and drink it. This, to me, is lunch.” But mostly Spin is for hot girls of a very specific type.

I’m sure you’ve seen them, skipping to class with a £50 water bottle and cycling shorts that would make Princess Diana blush, all brown hair honeyed with tasteful balayage, delicate tattoos of triangles on their inner forearms and little sprays of flowers on their ribcages – tattoos that can be hidden at their jobs in PR and corporate finance. Spin girls own £100 leggings with seams designed expressly to do impressive things to their butts. Struggling into a sports bra before my first class, under the harshest changing room lighting conceived by man, it was immediately clear that I was not among my people.

I had expected this, but that day still provided an uncomfortable welcome: no one else attending was, shall we say, at the start of their fitness journey. I felt like a walking “before” picture surrounded by dozens of possible afters, all of them named Amber. I had the novel experience of being quietly humiliated that I didn’t own anything mesh. Inside the studio, things weren’t much better; we were crammed in like underweight sardines, and the instructor opened the class by inviting everyone to “Really send energy to your ass, cuz it’s gonna need it!” Before I could inquire further, she was on the bike, explaining five hand positions and a resistance knob I felt certain I wouldn’t get the hang of within the 55-minute session. And then she turned the lights off, and I became a convert.

Many Spin classes operate in total or near darkness, something I had assumed was as much a stylistic flourish as the branded, watercolour-inspired leggings on sale in the lobby. To a certain extent, it is: the instructor will often adjust the lighting to illuminate him or herself during particularly tricky choreography, or jump off the bike to fiddle with the large votive candles spread throughout the studio, moving them around, blowing them out and relighting them to create ambience – with varying degrees of success. (Once, a male instructor blew out all the candles, flicked his lighter on and off, over and over, then told us to ask ourselves, “Are we a motherfucking Spin class or what?”) But I had not expected that turning the lights out would free me completely.

In the dark, I worked out harder than I ever had in my life. I felt no pressure to follow the choreography exactly, or to turn my resistance knob up to the recommended level. I cycled at a pace that worked for me. I laughed when the instructor suggested we should all try to stress less about money, wheezed my way up an enormous hill and somewhat unexpectedly wept, hard, during a particularly well-timed bit of Rihanna. I didn’t have to pretend that I thought it was cool when everyone twirled their towels over their heads like cheerleaders. I lost my mind when one instructor played a techno remix of Charlie Chaplin’s speech from The Great Dictator. But none of it mattered; no one could see. I wasn’t comparing myself with my ridiculously toned classmates, and didn’t feel I had to put on a show for them or meet their level, either. Why should I?

I couldn’t remember the last time I felt this unaware of my body, a body I’ve been letting others look at and judge, a body I’ve been looking at and judging myself since puberty, or before. In the dark, my physical form felt truly, blissfully neutral; it was not this unwieldy thing, sweating or turning red, or suffering any of the other indignities of physical exertion. Neither was it some kind of high-performance machine, bending to my will and looking amazing doing it. It was simply none of my business.

And yet, after months of twice-weekly classes, the only victories I noticed were internal: the ability to ride longer at a higher resistance, a sense of ease during a push-ups portion of class that had once left me breathless. My body was a little firmer, maybe, but not visibly so. I wasn’t ready to invest in a conch piercing or a fake tan or £100 cycling shorts. I couldn’t drum up interest in limiting my access to carbohydrates or wine with dinner, and so I looked basically the same as before.

It became clear that my post-breakup plans were unlikely to materialise: I would glow laterally at best. But I kept going, no longer in service of being seen, but to luxuriate in not being so. I know many if not most people attend Spin class because it makes their butts look good. But I’m sure there are others, like me, who are there because it makes them feel like their butt, and the rest of them, have dissolved into a fine mist.

At the end of a recent class, I ended up waiting for the same bus as my instructor. “You were in my class,” she said. I told her I didn’t realise she could see into the back row. “Oh, I see everything,” she said. “I noticed you because of how much you were smiling.”

This made me feel, in order: embarrassed, very embarrassed, embarrassed again, more embarrassed than I had thought possible, and then: emotionally overwhelmed to the point of tears. It is such a fraught thing, to be seen.

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