Executives at Peloton, the digital-fitness behemoth, speak about the company as though it were a Hollywood studio. The signature Peloton product is a pimped-out stationary bike, with a twenty-two-inch touch screen mounted above the handlebars, but the corporation’s crusade to become the “Netflix of wellness,” in the words of its chief content officer, rides in large part on the library of exercise programming that it streams from a multimillion-dollar production house in New York City. Since quadrupling its revenue during the pandemic, Peloton has suffered a streak of setbacks, among them hardware recalls, digital-security breaches, supply-chain snafus, management turnovers, advertising mishaps, and widespread reports of buyer’s remorse. Whatever the company’s future, though, its most lasting contribution to the culture may be its minting of a new generation of fitness icons for the digital age. Its magnetic cast of instructors, who stream slickly produced workouts for tens of thousands of live viewers and millions more on demand, are workout celebrities on a scale unseen since the heyday of Richard Simmons.

Like Sweetgreen salads or the Spice Girls, Peloton instructors come in defined varieties. For a mellow vibe, subscribers ride with Emma Lovewell, a former d.j. from Martha’s Vineyard with an older-sisterly wisdom and a cat named Kimchi. For chatter and distraction, they go to Cody Rigsby, a hunky riot who streamed classes from Pasadena during his stint on “Dancing with the Stars.” But the trainer most emblematic of the brand might be Robin Arzón, a forty-one-year-old “reformed lawyer turned ultra-marathoner,” who has been the company’s head instructor and vice-president of fitness programming since 2016. Arzón’s riders—I’m one of them—know to expect unrelenting interval workouts (they’re worse when she’s wearing yellow), nineties hip-hop, and breathless soliloquies on everything from besting fear to Burning Man, all delivered with brutal ebullience from Arzón’s flywheel pulpit as her long braid snaps behind her like a whip.

Arzón is fond of motivational slogans that sound at first like any other self-help-speak. Spend even a few minutes in one of her Together We Ride classes and you’ll almost certainly hear her say something like “Turn ‘Why me?’ into ‘Try me’ ” or “You will survive the fire—become the flame.” At least to me, though, her pronouncements usually have the feel of hard-earned principle. The daughter of a Puerto Rican lawyer and a Cuban refugee, she was a straight-A student who considered herself “allergic to exercise” until a freak event during her undergraduate years at N.Y.U. Arzón was at a wine bar in Chelsea one night in 2002, when a gunman strode in, poured kerosene on the crowd, and took her and dozens of other diners hostage. “The only things I was aware of were a gun pressed to my right temple, a barbecue lighter to my left, and my beige, urine-soaked slacks,” Arzón recalls in “Shut Up and Run,” her best-selling memoir-cum-manifesto, published in 2016. (The police ultimately intervened and arrested the assailant, who was sentenced to two hundred and forty years in prison.) In Arzón’s telling, the lingering trauma of that night is what moved her to pluck an old pair of sneakers from her closet and sign up for her first race. During the next decade, while earning a law degree at Villanova and practicing at a white-shoe firm in New York, she crammed her off hours with marathon training and fantasized about a new life as a fitness influencer. Since leaving her legal career, in 2012, she has become proof of her own aspirational mantras, with a million Instagram followers, a MasterClass on “Mental Strength,” and a “lifestyle membership club” called Swagger Society in the works. In “Shut Up and Run,” she writes, “I re-created myself, and so can you.”

Arzón has worked to expand what it means to be an athlete, developing prenatal workouts for Peloton during her first pregnancy—which she revealed, during a cycling class, in 2020—and publishing the fitness-focussed picture book “Strong Mama,” a Times best-seller. Her daughter, Athena, is almost two, and last month, on “Live with Kelly and Ryan,” Arzón announced that she is pregnant again. When we met recently, in a conference room inside a high-rise at Hudson Yards, near the Peloton studio, she was gearing up to promote a new picture book, “Strong Baby,” which will be published next week. Trailed by an executive assistant and a P.R. rep, Arzón wore an ankle-length slate shearling coat over a sparkly silver sports bra, black fish-net fitness leggings, and bedazzled white sneakers. In her bag was one of the “seventeen-ingredient” smoothies that her husband makes every day for breakfast. In our conversation, which has been edited for length and clarity, we discussed Peloton’s growing pains, the balance between public branding and privacy, and the long afterlife of trauma.

In your book, you recall working eighty-hour weeks in your old career, as a corporate litigator, and sometimes feeling that you were leading “a double life”: Robin the lawyer and Robin the athlete living passionately “twenty percent of the time.” Can you tell me how you went from quitting your day job to being hired as one of Peloton’s first instructors?

It was a slow two-year process. I was already running marathons, and I started to run ultramarathons, and I thought, Oh, my gosh, I love this—how am I going to live a life where I can do this all the time and still pay my rent in New York City? And I had an opportunity—I created an opportunity—to go to the London Olympics as a spectator, as a blogger, as a burgeoning social-media personality. I bought a ticket, put it on my credit card, and then two weeks later I was sleeping on my friend’s couch in East London.

I was doing all I could—petitioning P.R. agents, messaging athletes in their D.M.s on Twitter and just being, like, “Hi, I want to talk to you.” Literally anyone who would listen. I was just so passionate about it, this new career in movement. And in order to take this trip to London, I needed to quit my law job. I kind of had to choose. So I made the choice, and it felt like jumping off a cliff.

I had the luxury of time. And I had probably an irrational confidence that I was just gonna figure it out. In London, I actually received a job offer to work on the agency side, with Nike Women as my client, and I would be helping run their social-media networks. So I thought, Oh, my gosh, I’ve landed this plum job of storytelling in social media, which I was very enthralled with and using day to day. Influencer marketing, as it’s understood now, was kind of just starting.

I was in that job for about six months when I realized, like, I don’t want to hide behind a swoosh. I want to tell my story in partnership with these iconic brands. I left that job, and I just went out on my own. I created my first book proposal. I was training a lot of athletes at the time. I was living a classic multi-hyphenate life—teaching spin classes, working on my book, trying to get an agent, running ultramarathons. And that was when I read about Peloton.

I’ve read that you wrote to John Foley, the founder, cold.

I wrote to “info at”—so it was, like, “info@pelotoncycle.com.” And John was one of the first people I met when I came into the office. When I went in for my audition, there were probably twenty employees. So we were recording classes in the corner of the same place where all the executives and C-level folks sat. It was all very scrappy.

There was a recent ad campaign boasting that ninety-two per cent of users who sign up for Peloton stick with it through a year. But there have also been news stories about Peloton bikes being repurposed as clothes racks or languishing in secondhand-sale groups. Do you think the company has a sustainable future, given some of those doubts constantly swirling around?

The C-level folks are more attuned to that kind of stuff—you know, supply-chain stuff, any of that. But what I see is the heartbeat of Peloton is not going away. It’s getting louder. Like, you can bring up any meme you want. I don’t give a shit.

Every single day, every Peloton instructor is getting stopped, whether it’s at Duane Reade or wherever. And the interactions—sometimes they’re pleasantries, like, “Oh, I took your class. It was great.” Ninety per cent of the time, it’s “This is changing my life.” And I have not had a brand experience that was that meaningful, that palpable. So that’s what I focus on.