Though the conditions were far from ideal, Joanna Rohrback just had to Prancercise®. Sure, it was too humid outside. Yes, the location — a casino parking lot in Pompano Beach — was anything but bucolic. And of course, there wasn't any music. But Rohrback had an easy fix.

She popped open the trunk of her lima-bean-colored sedan, plunged a pair of thin and veiny arms inside, and withdrew what at first appeared to be a belt but was really much more. Tied onto its leather band was a small speaker and a Walkman cassette player. Wrapping the contraption around her size-five waist, the 60-year-old pushed play and declared it time to Prancercise®.

The Bee Gees song "Jive Talkin'" squeaked out of the speaker. Hearing this, the Prancercise® lady — the most famous pop YouTube sensation of this minute — broke into a toothy grin and began to trot, swinging her arms as though swimming the butterfly stroke.

A gray-haired gentleman ambling toward the Isle of Capri Casino on this overcast afternoon in June espied Rohrback galloping across the parking lot in spandex, two-pound anklets, and a neon-green shirt emblazoned with a cantering horse and nudged his stooped wife. They both pointed and laughed.

"Embarrassed?" asked Rohrback, who's amassed a cult following thanks to the revealing tightness of her spandex. "If my camel toe doesn't embarrass me, why would this? I'm not embarrassed at all!"

Though Prancercise® has been decades in the making, it only exploded into the national consciousness in late May after a video of Rohrback went viral. For several frantic days, the exercise, which mimics a horse's gait and is "induced by elation," clogged America's media outlets, teleporting this South Florida woman to instant fame.

During that wild ride, Rohrback taught Al Roker to Prancercise® on the Today Show. She netted write-ups in Newsweek, the Wall Street Journal, and New York magazine. She starred in John Mayer's new music video. Her YouTube clip shot from 500 views in mid-May to 7.3 million — more than any track on Kanye West's new album, Yeezus.

The reasons behind this incredible trajectory are simple and complex. The simple first: Rohrback is captivating. She has glass-blue eyes and tragically beautiful features, like a Charles Bukowski character or a Cindy Sherman photograph. She speaks in a reedy twang that immediately distinguishes her as a native New Yorker. She exclusively wears spandex and ankle weights that at first are strange to behold but then become an ordinary extension of her being.

Then there's Prancercise®, quite possibly the most sincerely honest, if ridiculous, exercise ever notched into the annals of fitness.

The other reasons are more subtle. Five years ago, we would never have known Rohrback or Prancercise®, and her sudden emergence represents a new age of celebrity. YouTube fame can befall any person at any time, make him or her a champion or a fool, and turn lives topsy-turvy. It's unpredictable. It's dangerous. The wolves on the internet can turn on you.

Rohrback has waited her entire life for this taste of celebrity and wants more of it, but that pursuit is at odds with her personality. An intensely private person, Rohrback doesn't want anyone to know anything about her beyond Prancercise®. Not where she shoots her videos, what car she drives, or how she makes her money. Threatening "legal repercussions," she declines to specify where she lives beyond "the Coral Springs area."

So can this shy person withstand the full monty of internet fame? Will it suck her up and spit her into a pool of one-hit wonders? Will anyone remember Prancercise® in six weeks?

Rohrback thinks they will. In fact, she's sure of it.

"Let me tell you what I see when I see this," says Rohrback, overlooking the horse tracks at the Isle of Capri. "I don't see people enslaving horses running them around the track. I see 100 people Prancercising to Motown in unison. Wouldn't that be wonderful? Wow, just imagine. It can really happen."

Ten days after the video went viral, a humid afternoon arrived. Careening across a sun-splattered park on Lyons Road in Coconut Creek, Rohrback glowed from excessive Prancercise®. There was a tattooed, short-haired British cameraman named Jay Morris nearby, filming her fluttering arms. Morris had flown in from London the night before to interview Rohrback for a British television show called Rude Tube. He can't stop telling the 101-pound woman how perfect and fabulous she is.

Rohrback shrugged, coyly cocked her head, and looked pleased. "Really, you think so?" she murmured, dozens of tiny wrinkles around her mouth crinkling. "Thank you."

"You're doing great, Jo!" Rohrback's gray-haired friend Sharon Schwartz bellowed from her perch at a nearby picnic table. "I'm heavier-set and have a bad ankle," lamented Schwartz. "I can't Prancercise®. I could never do what Joanna does. Just look at how cute she looks."

In this moment, celebrity seemed like a pretty good fit for Joanna Rohrback. She beamed like a kid showing off cartwheels for adoring parents.

Rohrback was clad in her Prancercise® uniform: black spandex, black tennies, feathered hair hanging shoulder length, neon-green long-sleeved shirt rolled up to the elbows. Over the course of one month that New Times spent with the Prancercise® creator, attending local casinos, Starbucks, and flea markets, this was the only outfit she ever wore.

Rohrback cannot overemphasize the importance of brand maintenance. She trademarked the term Prancercise® and founded Prancercise LLC last year and frets over scenarios of intellectual property theft. (She warned New Times that to be on the safe side of a potential legal thicket, we'd better trademark Prancercise®. Other media outlets have not, and she's currently consulting her legal team, she says, to see what there is to be done about that.)

Rohrback was attempting to explain such concerns to Morris, who was urging her to unveil the hidden nucleus of Prancercise®. "Could you give us a little tutorial?" pressed Morris, who was traveling the nation interviewing pop internet sensations. After Rohrback, he was scheduled to interview a rapping realtor in San Diego, whom Rohrback and Schwartz agreed sounded quite interesting.

"But how does one actually Prancercise®?" Morris asked again. Rohrback stopped prancing. Her heavily made-up face was suddenly severe. This, she informed Morris, was something she cannot provide Rude Tube. "I need to sell my book," she said, referring to her recently self-published instructional manual, Prancercise®: The Art of Physical and Spiritual Excellence, available for $23.36 from Amazon. "I can't just teach people how to Prancercise® for free, you know."

Her book does, in fact, go into granular detail to convey Prancercise®. It explains something called the "Prancewalk." This requires many "elongated strides," "rotated hips," and arm motions that are both "graceful and rhythmic." Afterward follows the "Prancetrot" — referred to in formal settings as the "Prancercise®trot." This one isn't for beginners, Rohrback cautions, advising care when attempting such maneuvers. The "Prancetrot" demands a "combination of quick-step consecutive steps" amid a flurry of flailing arms. Finally there's the "Prancegallop," an acrobatic achievement that calls for "springing high off the ground... like leaping in the air."

P90X fanatics need not apply. "I think it's a nice beginners' workout," famed fitness guru Richard Simmons told New Times. "If you look at a lot of videos out there, it's only tough-looking people going harder and faster and stronger. But with Joanna and I, it only leads to smiles and rainbows — not thunder."

Simmons, speaking from his Los Angeles residence, began to weep into the telephone and took several deep breaths to calm himself. "You can tell that what Joanna does comes from her soul, and that's what makes her stand out. She's precious. If she was here, I'd do her nails."

Prancercise® first came to Joanna Rohrback at a time of great despondence.

The year was 1989. As Rohrback tells it: "It was three months earlier that I'd broken off my engagement to marry a handsome and charming Jewish dentist." His name was Mitchell Feuer. He lived in Hollywood. And to Rohrback, he wasn't exactly Johnny Depp. "Each boring day had led to another boring week and month," she writes in her self-published book, which has sold hundreds of copies since her video took off. Rohrback says her creative energies were too robust for the trappings of traditional, married life: the shopping lists, the cleaning responsibilities, the pressure to have kids. She had to get out. But how?

She left Feuer (who didn't respond to requests for comment for this article) and moved into a rundown studio apartment near Hollywood Beach, which she considered a "prime location" for imaginative endeavors. Most important, the Broadwalk, a wide pedestrian avenue with blue-collar mom-and-pop shops on one side and turquoise waters on the other, was "a haven for exercise fanatics like myself," Rohrback writes. She settled into a new life of adventure and "set the stage for the creation of Prancercising."

On a clear morning at 7 soon after, Rohrback was power-walking down the Broadwalk when serendipity struck.

She had on a pair of headphones, and a Motown cassette was spinning inside her Walkman. A "really great" song that Rohrback can't recall came on, and its infectious beat overpowered her senses. Over the next few moments, it's unclear what, precisely, happened. What she remembers is this: She began to prance — yes, prance. Shimmying to that Motown groove, she swung her arms backward, stepped back and forth, and summoned an equine spirit to guide her gallop. Her breast swelled with feeling. This was neither dance nor exercise.

"My life had changed forever," she says. From then on, from failed romances to addiction to illness, she overcame a sometimes rocky life nurturing an unwavering belief that she, Joanna Rohrback, had been destined for something profound and beautiful and unusual. And that something was Prancercise®. "I've never had children," she sighs — but not mournfully. "It's just me and three feral cats. Prancercise® is the only baby I've ever had. I'm all alone, and I have no support system."

But then she brightens. She always brightens. "I've been alone a lot in my life, but I've never been lonely, you know? There's a difference."

Rohrback, who graduated with a health sciences degree from Florida Atlantic University in 1978, quit her job as a Broward County realtor soon after the Prancercise® discovery. All she could think about, restless inside her beach studio, was her invention. She conducted it every day for at least an hour, taking years to hone its every gesture and kick. The discovery of Prancercise® was extemporaneous, she admonishes, but its beauty took work.

"For a long time, Prancercise® was kept under wraps," says Rohrback's longtime friend Joyce Brobeck, a massage therapist in Fort Lauderdale. "She's a very private person, and she was always worried about people stealing it... She had the keys to the Hilton Gym [on Hallandale Boulevard] and only came in early and late. I didn't see the whole thing until she showed me and the others outside of the gym. It was beautiful."

Rohrback doesn't like elucidating how she survived those years. "Do people need to know everything about me?" she asked New Times, pausing. "It was credit cards and savings." (Brobeck mused that Rorhback's father, who worked as an attorney in New York and died young, had left her well off. Rohrback denies that theory.)

She also kept Prancercise® hush-hush. In 1994, she moved in with her mother, who'd been diagnosed with Parkinson's, in Coral Springs and furtively wrote her book, which became equal parts instructional manual and memoir. But she couldn't find a publisher who understood its vision, and as her mother melted into sickness, both the exercise and written work languished. "She took care of her mother all by herself," friend Josie Marinello, 94, remembers. "She has two sisters, but they didn't volunteer anything; all of the pressure was on Joanna." Rohrback no longer speaks to her sisters.

Rohrback's mother died in 2004, and in the aftermath, the Prancercise®-er developed a severe "feminine condition" that she mentions frequently but almost aggressively declines to identify. She was too sick to find consistent work, she says, and became a regular, then a high roller, at casinos across Broward. "I couldn't Prancercise®!" she erupts over a bottle of Fiji Water inside a darkened VIP chamber at the Isle of Capri. "I couldn't be creative; what else was I supposed to do? ... I lost a lot of money. In five years, there was only one when I actually made any money."

Then, with Rohrback once more at her lowest, Prancercise® again galloped to the rescue. In 2011, her feminine condition began a slow remission. "I healed myself," Rohrback explains, declining to elaborate. Soon she was prancing the beaches of South Florida, teeth agleam. It was time, Rohrback thought, to take this thing public — with or without the publishers. So that fall, she got her trademarks and put up an advertisement on Craigs­list asking for help designing her book cover.

"We met at a Dunkin' Donuts," remembers Eric Gzimalowski, a blond 26-year-old photographer in Coral Springs. "She said she wanted to get some photos of her, quote, exercise routine. She was very, very confidential and never once used the term Prancercise®. It was crazy."

It got crazier. She pushed across the table a tizzy of legal documents. "It was some sort of documentation saying I wouldn't sign or steal or sell or copyright anything from her book. She was very, very strict. I was dumbfounded, and then I signed it."

Rohrback's directions for the cover of her book were specific: She wanted clouds and fields and horses. And at the center of the idyll, she directed Gzimalowski to superimpose photographs of her squeezed inside spandex and anklets, mid-Prancercise®. "She said she wanted her movement to be whimsical. I wouldn't say she's controlling, but she's a woman who's extremely passionate about Prancercise®." She paid him $150.

On a cloudy winter day soon after, Rohrback enlisted a tanned Miami cameraman named William Brito, who climbed into a golf cart at a country club in Tamarac and shot Rohrback Prancercising under the palm trees. "We're gonna really cut the noose and let it loose!" squealed Rohrback, trotting in white tights. "Let's stop talkin' and do some walkin.' Afterward, she chose a four-chord rock song to accompany the video, and then, on Christmas Day last year, it went live on YouTube.

Prancercise® now belonged to the masses.

Months of silence later, on May 25 in East London, a ponytailed bloke named Edwin Stratton, who was once the drummer of the prominent English band One Minute Silence, was scrolling through the Reddit subforum "WTF" when he saw an image he'll never forget.

An anonymous user had posted the image of a book cover, which showed a white woman hovering above green fields aside a galloping white stallion. It was absurd. He loved it. "The cover was superb," he tells New Times. "So I looked for a video on YouTube, which I was delighted to find actually existed."

At 1:14 a.m. that night, Stratton tweeted the Prancercise® video to British comedian/blogger Robert Popper, who had blogged about a new Estonian fitness routine called "Horsebic" that, incredibly enough, also impersonates a horse's mannerisms. Popper watched the clip of Rohrback prancing through the Tamarac country club, thought of Horsebic, and blasted a quick post on May 27. "Prancercise® is some kind of special!" he croons to New Times.

Things then happened very fast. Lauren Kirby, a young brunet who freelances at Buzzfeed, saw the video on a private Facebook group with her friends. "And when I saw it, I knew it was viral material," she says. On May 28, Prancercise® materialized on Buzzfeed, under the category "Because Yes." The website Videogum, fecund ground for many bloggers, also punched in a story that day, and Prancercise® went supernova. (Even New Times got into the mix, on May 29, heading our take: "Florida Woman Invents Insane 'Prancercise.' ")

At the time, Rohrback was closely monitoring its rapid progression from her one-story hovel in the "Coral Springs area." "At first, I thought it was some kind of mistake," she says. "But then I saw the Huffington Post had written something, and I knew it had gone viral." Rohrback contends her video took off "because of the uniqueness of the program; no one had ever seen such movement." And while there's no denying that, the additional reasons for its popularity are much more complicated.

To understand what made Prancercise® go bang on the internet, one must first understand that today, sharing is everything. Videos, stories, songs — anything that makes us feel something — serve as carrier packages of raw emotion that we parcel to our virtual community. We delight in spreading the content as though it's hot gossip.

"We're in the business of getting people to feel primal emotions that don't require a lot of thought," says Gawker's viral wizard, senior editor Neetzan Zimmerman. "That's where the money is. With a video or an image, you're going above words into the very essence of the reader and hitting them directly in those areas where they can't control. And people share [content] when those emotions are triggered."

Especially if certain "arousal emotions" — anger, awe, anxiety, or humor — are stimulated, a University of Pennsylvania professor named Jonah Berger wrote in 2011 after scrutinizing the emotive impact of the most emailed articles from the New York Times. The internet, his research suggests, has become a modern means to satisfy ancient social instincts. Words and long stories (like this one) are lousy vehicles of feeling, but short videos and pictures that can isolate one pure emotion? Boom.

In the past two years, viral videos have amassed such global import that they've shaped nations, anointed stars, and initiated worldwide manhunts. Two springs ago, Invisible Children disgorged a video explaining how Uganda's former tyrannical president, Joseph Kony, conscripted 66,000 children into military service. The short documentary triggered sweeping outrage, netted more than 100 million views, and marshaled a worldwide movement calling for Kony's arrest. (He remains at large.) Or Rebecca Black became famous overnight when her YouTube video for the song "Friday" garnered millions of views in 2011. Her song — derided as the "worst song ever" by E! — led to real-world record sales but also death threats and mockery. (Just last week, Black released a Miley Cyrus cover and grabbed fawning reviews from the Huffington Post and MTV.)

In Joanna Rohrback's case, the driving emotion was pure humor — but were people laughing with her or at her? "OMG this is just so wrong it's right!" bleated one commenter on Buzzfeed. "The wig, the camel toe, the awful music, let alone the prancing! Thank you so much; I needed this laugh!!!" Another wrote: "the Prancercise gallop hahahahahah." Within a day or two, the YouTube parodies started rolling in. The spoof "Prancercise From Head to Camel Toe!" featured a blond comedian named Beth Hoyt living in Brooklyn. "This is about finding your inner camel toe," Hoyt admonishes, gyrating in blue spandex. "It cannot be too big. Improvise if you have to. I used socks. It helps work your inner thighs."

Haters gonna hate, parries Rohrback, who at the time was unfamiliar with the vernacular of camel toes. Days after the viral explosion, she scuttled into the VIP section at the Isle of Capri, eyes wide and azure. "I don't pay attention to the neighsayers," she announced. "Get it? N-E-I-G-H. It doesn't bother me at all. I've always been special, and now all these people are finally noticing it. And I just wanna tell 'em, 'What took you so long?' " Then her voice lowered. She looked around. There are concerns, she whispered.

"Someone's been leaving these nasty comments under my video and on my [Amazon] page," she says. "Someone else hacked into my email. It must be my competitors — Jazzercise and Zumba. Who else could it be? They're jealous."

Later, while setting up her Skype account amid the frenzy of the Isle of Capri poker room, she worried that another fitness group bent on trickery would somehow obtain her password. Her friend Sharon Schwartz agreed: "Jazzercise is the arch nemesis of Prancercise®. Jazzercise cannot hold a candle to Prancercise®."

(Reached for comment at Jazzercise HQ in Carlsbad, California, a spokesperson denied allegations that Jazzercise was plotting against Prancercise®. "We think Prancercise® can stand on its own merit," said Michelle Escala, adding she didn't know whether any inter-fitness-program sabotage had ever occurred. "Internally at Jazzercise, we've had a laugh at Prancercise®, but it hasn't gone any further than that.")

This paranoia isn't unusual. Gawker's Zimmerman says immediate fame can be terrifying and addicting. He "very consciously" passed on writing about Prancercise®. There was a rare sincerity in Rohrback, he says, that didn't deserve the dark repercussions of internet notoriety.

Rohrback "could be any person with any name from anywhere in the world," he says. "It's that action that propels [someone like her] into fame, but as soon as we find the next thing, we just move on. They try to recover, but they'll never again re-create it no matter how hard they try. It's just serendipity. And it hits them hard... I wouldn't wish it on my worst enemy."

By now, you know the four points of Prancercise®," Rohrback stuttered into the camera at an undisclosed location in western Broward. She wore black tights and a white blouse, but her expression didn't carry any of that cocky delight that made her first video a hit.

"However, what about a prance to romance to?" Rohrback murmured, barely looking into the camera. "If you're pregnant or nursing, you should consult a physician before you romancercize."

The shot fades out, picking up with Rohrback trotting the leafy streets to "Paper Doll," John Mayer's first single off his new album, Paradise Valley. As Rohrback tells it, Mayer, who never spoke to Rohrback, had been working on the song when he saw the Prancercise® clip on mute. "He realized his song synced perfectly to my movement," she says.

In Mayer's video, her gallop is described as "Advanced Prancercise®." At one point, an image flashes of a man named "Jarrad Rohrback" in subtitles. Though the song's slow-dance beat is antithetical to the Prancercise® ethos — which is high-energy and effervescent — this partnership with the rock singer, released on June 18, hit the national media like an atomic bomb. And Rohrback, who had been worried about her fading media attention, was suddenly back. "Everything had really gone into a lull there for a few days, and I told her, just wait until this video comes out," Schwartz remembers telling Rohrback.

Rohrback's phone was again aglow with interview requests from Rolling Stone and CNN. But it was different this time. Rohrback felt tricked. "They didn't tell me they were going to use 'Advanced Prancercise®'! There's no such thing as 'Advanced Prancercise®'! They made that up. They also didn't tell me they were going to use my last name. They were just feeding me lines."

And "there is no Jarrad Rohrback!" she says. "I was naive to trust them. I was not happy with how they edited it." (Rohrback declined to reveal how much the musician paid her but declared it a "substantial amount.")

Rohrback felt "in a state of confusion." She adored her growing number of fans; she'd waited decades for all of this attention — so why did she miss her old life? Did anyone realize Prancercise® was a creation of sincerity? Had she been a fool?

Days later, Rohrback's phone chirped. It was the promotions manager at the Seminole Casino Coconut Creek. Rohrback was scheduled to perform a Prancercise® show there that night. She hoped to sell some shirts and books and to show the exercise was more than a gag.

But after she hung up the phone, she seethed, "I'm not a happy camper! I'd thought it was going to be just me Prancercising, but now I find out it's going to be a competition, and I'm the judge."

Still, Rohrback arrived at the casino smiling wide. A phalanx of photographers from Getty Images and the Associated Press fanned out before her, bulbs flashing. Rohrback, in heavy makeup and neon green, preened. Schwartz, wearing the same outfit, settled in at a table at the front, the two of them looking like boxer and manager before a fight. They'd recently had a spat over the direction of Prancercise® but had now made up. Schwartz guarded the books and T-shirts like fine jewels.

Rohrback was squinting into the flashing lights when a brown-haired woman jostled her arm. Time to get backstage, she told Rohrback. The contest was about to begin.

The room fell dark. The four-chord rock song from Rohrback's video boomed from the concert speakers. Three dancers wearing pink — two blond women and a buff guy — fluttered on stage and began to Prancercise®. But they kicked their feet and waved their arms all wrong. The British casino moderator, teeth big and yellow, bloviated into the mic. A crowd of 60 people swelled around the stage.

"I love Joanna because of her style — but c'mon, this is all just about the camel toe!" one young and twitching man said.

Everyone laughed except Schwartz. The gray-haired woman turned her head away from the air-humping dancers. "This isn't Prancercise®," she whispered. "I'm so happy Joanna can't see this. She'd hate this."

Afterward, five bedraggled casino regulars stumbled onstage and attempted to out-Prancercise® one another and win $1,000 in free slot play. One man in a baseball cap, who looked aged and dazed, jerked his walking cane back and forth. The crowd heckled the buffoonery.

Finally, Rohrback stepped out to face the throng. The cameras flashed for several long minutes. She took the microphone in a thin hand and, giggling, anointed a woman with long, sinewy hair the winner. After the performances, nearing midnight, Rohrback refused to let the glow of the night fade. She slowly gathered the T-shirts and Prancercise® books. During the entire night, she's sold only a few. "Gamblers aren't into holistic healing," she said.

Then she brightened. Joanna Rohrback always brightens.

On a recent weeknight at 9, as the lights are blinking out near Coral Springs, Rohrback steps out onto the street wearing spandex and ankle weights. She hasn't had the chance to Prancercise® all day.

She fits on a pair of headphones, hits play on a Bee Gees mix tape, and gallops into the darkness. While some women would worry if out alone at night, Rohrback is bereft of concern. She has Prancercise®. The exercise, she says, will protect her. "Prancercise® is uninhibited," she says. "I don't feel scared doing it. I always feel light. All the stress in my life passes, and I feel empowered. I feel awe."

And perhaps this is the power of Prancercise®. It's not intended to get you ripped or marathon-ready. It's meant to make you feel weightless. That's why Rohrback was so adamant about hovering on her book cover. When you trot like a horse, you lose yourself in the absurdity of the act, and every worry suddenly dissolves. It's why Rohrback loves Prancercise® and why it returns to her at times she needs it most.

Richard Simmons was right. "Joanna's like Judy Garland walking down the yellow brick road. When I started, everyone laughed at me too, because I'm certainly not a handsome person. All the handsome men and women laughed at me and told me I'd never make it. But people who succeed are those who are persistent."

Forty-five minutes after Rohrback began her Prancercise® loop through the streets, she returns to her house. She can't Prancercise® as far she used to. "I'm 60 years old now," she says. Taking long equine strides, she steps up to her door and walks inside her house. She has no idea how many calories she just burned, and she doesn't care.