One afternoon in 1987, while working as a trainer at a Jack LaLanne gym in Plainfield, N.J., Terri Walsh received an invitation to interview at the chain’s most exclusive club, a renovated parking garage on 61st Street where well-heeled Upper East Siders traded stiletto pumps for Reebok sneakers. When Ms. Walsh arrived, the Vertical Club throbbed with music spilling out from the aerobics studio on the second floor. Through a pair of glass doors below a brick archway, she “walked right into the heart of everything,” she said.

When the club’s training manager, Ralph Raiola, gave her the tour, she recognized celebrities working out with charismatic, hard-bodied trainers. The locker rooms were tawny wood, stocked with designer cosmetics and hotel soaps. There was a juice bar near the pool. Overwhelmed by the club’s extravagance, Ms. Walsh turned the job down. Two weeks later, she realized her mistake, called Mr. Raiola, returned and remained for four years.

As one of the club’s first female personal trainers, Ms. Walsh’s work uniform became two pairs of black tights, a belted thong leotard, leg warmers and sneakers. She joined a phalanx of bright young things recruited for their aspirational bodies and fitness expertise, educated within an inch of their lives to train some of the most demanding people on the planet: New York’s upper crust.

During the mid-1980s, the Vertical maintained its razzle-dazzle reputation by staying ahead of fitness trends; some of its innovations helped lay the groundwork for spaces like Equinox, SoulCycle and Barry’s Bootcamp that redrew the city’s landscape (and now, with the pandemic’s strictures against sweaty congregation, stand hanging in the balance).

Along with Sports Connection in Los Angeles and the East Bank Club in Chicago, the Vertical Club was one of the first health clubs in the United States where, as early as 1984, you could do aerobics, use a Nautilus machine, play tennis or squash, run around an indoor track, do yoga or tai chi, go swimming, get a massage, and work with a personal trainer under the same roof (the rock wall came later, in 1990). Mr. Raiola created an early one-on-one personal training program in New York; it became a dominant fitness trend of the ’90s, notably at the David Barton Gym.

The Vertical Club attracted celebrities (like Cher, Diana Ross, Liza Minnelli and Arnold Schwarzenegger); executives (S.I. Newhouse, Edgar Bronfman Sr.); pro athletes (Keith Hernandez, Andre Agassi); musicians (David Bowie, Mick Jagger, Nickolas Ashford and Valerie Simpson, who was trying to become “solid … as a rock,” presumably); and models (Fabio, Brooke Shields, a whole flotilla from the Ford agency). Tom DiNatale, the club’s dapper general manager, was there to greet them, wearing a designer suit and smelling divine. ‘’People come to see and be seen,’‘ he told The Times in 1984.

There was no V.I.P. area, so these familiar faces worked out with everybody else. “I don’t know why it became such a magnet for celebrities,” said Annie Niland, the club’s aerobics coordinator from 1985 to 1988, though, “for the most part, everyone was very cool about it.”

Billie Jean King, who coached Tim Mayotte on the fourth-floor tennis courts, remembers the club fondly. “They were ahead of their time,” she said. Garage doors rolled up around the perimeter of the courts, creating an open-air effect on balmy afternoons, several stories above the city. “It was a really solid fitness facility, but it was also a great place to hang out.”

Virtue and Vice

In the evenings, the Vertical catered to its night-crawler clientele, who exercised with the same intensity they brought to the Tunnel and the Palladium on the weekends. (“Jesus, don’t go there at five o’clock. It’s insane,” Mr. Hernandez told The Village Voice in 1987, adding an expletive.) Many were Studio 54 alumni who’d aged out of nightlife and found an outlet in fitness. Several nights a week, they bounced, twisted and gyrated to Donna Summer and Sylvester under the flashing neon of the Vertical’s aerobics studio, where instructors taught 100-odd people from a stage with a microphone, their bodies projected above on a giant screen. Michael Paoletta, a downtown D.J., supplied the mixtapes.

Monday was the big night. Around 5 p.m., ladies would line up at the coat check to shed their furs, revealing Day-Glo leotards and tights. Hair piled high, makeup piled on, unafraid of deflating or melting, they took a cue from High Voltage, a.k.a. Kathie Dolgin, the club’s so-called “exertainment director” in 1984, who favored sequined leg warmers and a lightning bolt across her chest. “I always wore glitter,” Ms. Dolgin said. “You could tell what equipment I worked out on, because you could follow the glitter.”

The ’80s were a “work hard, play hard decade,” said Shelly McKenzie, a fitness historian. In the ’70s, many Fortune 500 companies installed workplace gyms. As a result, gym goers were seen as “confident, capable, industrious people who really had their acts together,” she said. And don’t forget: “women are climbing the corporate ladder in the ’80s.”

Aside from those office gyms, New York fitness spaces were often considered “grimy” bodybuilding spots or cruising venues for gay men, stigmatized during the AIDS crisis. The Vertical Club, its name suggesting “the up and up,” brought in the light.

The obvious glamour of the club tinctured virtue with vice, “bolstering that image that this was sexy, this was a singles club, this was where people went to meet each other,” said Natalia Mehlman Petrzela, another fitness historian. “But at the same time they had to sanitize that image, because they wanted to attract this white-collar clientele.”

Big Fitness continues to walk that line today. “We see that with instructors who are very risqué in the language they use when talking to riders and students,” Ms. Petrzela said. Cheeky marketing language often foregrounds sex appeal. At Barry’s Bootcamp, the red lights evoke a red-light district. “On the other hand,” Ms. Petrzela said, “you’re engaging in this disciplined pursuit of health, which is the most culturally sanctioned thing we have.”

Case in point: In 2017, the infamous nightclub The Limelight reopened as Limelight Fitness.

Connecting and Disconnecting

Mornings and afternoons at the Vertical Club were prime time for networking. At one point, staff kept white slips of paper at reception for members to write down each other’s phone numbers. “A lot of business connections were made there,” said Julie Cirillo Milliron, the club’s director of fitness from 1988 to 1993, who taught downtown at Joy of Movement and Pineapple before she was recruited.

In 1984, it cost $1,150, according to The Times, and $4,000 for the tennis program; some people would save up all year for a membership to gain access. “You had a real cross-section of New York,” said Gay Talese, the author, from teachers and firefighters to lawyers and civil servants, with varying interests and education levels. “You met all kinds of people,” he said, who “were really paying attention to one another, and not diverting their attention to some little hand-held gadget.”

Because there were no smartphones or television, there was nowhere to look but in the mirrors surrounding the gauntlet of Cybex cardio machines, at oneself or someone else. “To be very blunt about it, it was kind of an elevated pickup joint of well-exercised people,” Mr. Talese said. (Ms. Niland met her husband there.) From the basement pool and juice bar, to the roof deck and restaurant, there were plenty of places to hang out.

Today, “many boutique studios will ask you to put your phone in your locker, or tell you to put it away, so in some ways I think they try to recreate that experience where you’re engaged and in the moment,” said Liz Plosser, the editor in chief of Women’s Health magazine, who has been aware of the Vertical for as long as she can remember. Pre-pandemic, she said, “many gyms and boutique studios became this gathering place for people to find community.” For some, “it’s supplanted going out to coffee with friends.” Last March, those spaces closed and fitness migrated online, united by the influence of “super-instructors” on platforms like Zoom, Instagram and Peloton.

Several Vertical Club staffers, like High Voltage, became their era’s equivalent of influencers, at least locally, because media and entertainment executives went to the club. (Plus, “no one wants to hang out for an hour with someone who’s boring,” Ms. Walsh said.) Personal trainers needed fitness expertise to work there, like martial arts backgrounds, powerlifting accolades or Columbia University physiology degrees.

In the late ’80s, aerobics instructors made $50 to $60 an hour, and trainers made more; at competing gyms, aerobics teachers made $12 an hour. Rents in the city were low — Ms. Walsh paid $417 for a studio apartment, less than $1,000 in today’s dollars — allowing personal training to become a real career. Some staffers went on to have successful careers in sports and fitness; the Vertical’s tennis pro Jill Smoller, who played with Ms. King, is now Serena Williams’s agent at WME.

‘Not About Wellness’

In the early ’80s, “aerobics was such a new industry, it attracted dancers and people on the cusp of show business,” Ms. Niland said. “We were waiting for the next big dance job, and this served a purpose, so it was very show business-oriented. It was not about wellness the way it is now.” Groups of instructors competed in aerobics competitions at the Palladium nightclub. “All of our following came, and it was a really big deal,” she said.

At the club, Ms. Walsh was scouted for TV commercials and modeling jobs by Reebok, Nike and DKNY. She also walked a Donna Karan show in New York Fashion Week, because her muscle tone was en vogue. Ms. Cirillo Milliron appeared in Vogue, Harper’s Bazaar and People. “I never paid for a meal,” she said. “Every time I went out, they were like, ‘oh that’s right, you’re from the Vertical Club.’” At Le Cirque, Sirio Maccioni, the owner, would take a table from the back room and put it in the front of the restaurant for her, “because the club was such an integral part of life on the Upper East Side.”

By her account, the members were “the most generous people in the world.” They routinely donated to charity drives (which some, like the designer Mary McFadden, helped organize), and offered their services to staff at a discounted rate. “A lot of them were doctors, psychiatrists and dentists, and we had kids working the front desk who didn’t have a lot of money,” Ms. Cirillo Milliron said. “Those doctors saw those kids for free because they were Vertical Club people.” Trainers traveled with their clients and spent time at their homes in the Hamptons.

However, staff often brushed off members’ advances, too. “I had a guy invite me to lunch and offer to set me up in an apartment and pay for me to go to school, if I would just ‘see’ him twice a week,” Ms. Walsh said, characterizing it as a “Me Too” experience. “I almost burst into tears. I just wanted to work.”

Teaching aerobics, “we were like little rock stars up on the stage,” Ms. Niland said. “It was all about how we looked, which for me brought the same neuroses that it would when you’re an actress.”

Ms. Petrzela has no doubt women were objectified at the Vertical, but notes that fitness was still radical at the time, since society was “only a few years past the dominant scientific theory saying if women exercise too rigorously, their uterus will stop functioning, or they’re ‘going to get muscles and look like men,’” she said. “It was a big deal for women to get together and move strenuously. It was a big deal for women and men to work out in mixed settings together.”

According to Ms. McKenzie, the ’80s gym became the third place, “where you get the ‘Cheers’ effect, where you walk in and you know people and you feel a sense of belonging, maybe you don’t know them particularly well, but it makes you feel grounded in your neighborhood or your city.” In the 2010s, that feeling was starting to disappear in cities because of ClassPass, the app allowing users to try out different gyms and studios.

The Flattening of Fitness

After opening a few satellite clubs that diluted the brand, the Vertical Club lost momentum. In the early ’90s, flamboyant spandex fell out of style and the more low-key Barton gym gained traction. The celebrity cache caught up with the Vertical, too; bridge-and-tunnel folks would commute in hopes of seeing Sylvester Stallone on the StairMaster, so the names left.

Prices began to drop; in 1990, membership was $62 per month, plus a $750 initiation fee. In 1991, it became the first in New York to install Health Club Television, to members’ chagrin. And staff left — Ms. Walsh became the creative director of programming at the growing Crunch Fitness chain, which sold a message of inclusion and acceptance rather than exclusivity. (Now she teaches resistance training over Zoom from her studio in Costa Rica.)

The AIDS crisis had a significant impact. Many of the gay male instructors on staff died of the disease, Ms. Niland recalled. “It was devastating,” she said, because it happened slowly. “You would hear about one instructor being ill, and they didn’t know what it was, then it was another instructor, and by the mid-90s, the staff was decimated.”

In 1999, the club closed for good. (The original space is now an Equinox.)

Places like the Vertical are often forgotten because of scant paper trails. “There are very few places where you can go to see what was on the schedule in 1978 or who was teaching what; records are really hard to find about individual gyms,” Ms. McKenzie said. Plus, the celebrity presence discouraged photography. Very few images of the Vertical Club exist.

It’s hard to imagine a place like the Vertical operating now, in an era where mundane celebrity interactions are chronicled on anonymously run Instagram accounts. There are echoes in places like SoHo House and Dogpound, the downtown gym where Victoria’s Secret models are known to train.

When and if we finally return to gyms, digitally fatigued from months of lockdown, might they resemble the screenless scenes of yore? “Given how strong the desire is for fitness, and for that kind of connection that existed before the pandemic, I can imagine spaces that are more like social clubs, where the gym is one part of it but not even the primary part,” Ms. Petrzela said.

That was the Vertical Club, where the ego and psyche got as much of a workout as muscles and heart. “Yes, they were into fitness, but it was more about the vibe of being there,” Ms. Niland said.

By spending morning, noon and night between those walls, Mr. Talese said, “you really could escape whatever you wanted to escape.”