(ABC News) -- Neon lights flashed across the dark room as a group of women fist-pumped the air, stomped their feet and bounced their hips to the beat of Beyonce's "Get Me Bodied."
It was not the middle of the night, and these women were not in a nightclub.
It was 2:30 in the afternoon on a Saturday in Brooklyn, and they were shaking everything they have -- for a workout class.
The Vixen Workout, an hour-long, high-cardio "twerk out" class for women, is fresh out of Miami and is the hottest trend in the dance fitness world.
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Developed by former Miami Heat dancer Janet Jones, the Vixen Workout is about feeling hot, raising women's spirits and giving them power while dancing and sweating to club music. Jones, 32, said she created the class to help women get their sexy back.
"When we go out to a nightclub, and all of us were feeling like we couldn't even move because we're someone's mom or someone's boss or something, and that's when I had kind of a moment: What if I created something that lets women feel safe to let loose and dance and be a little rebellious and at the same time lose weight," she said.
The Vixen Workout gained popularity through word of mouth, and now 1,500 women sign up to shake their curves with confidence, and they have the selfies to prove it. Jones calls the women who take her class part of the Vixen Army and encourages them to use Instagram and other social media to post photos of themselves during and after class. More than 11,000 photos with the hashtag "VixenArmy" have been uploaded to Instagram.
"What will happen is the girls will take selfies of themselves in my class, and then their friends on their Instagram feeds will be like, 'Where are you? What are you doing? Why do you look so great? Why do you look so happy?' And they would just share their experience," Jones said. "So it's really like girls that we call the Vixen Army kind of have self-promoted the class just because they had such a good time and they want to share it with their friends."
No frumpy sweatshirts in the Vixen Workout class. Jones encourages women taking the class to come with makeup on, hair down and heels on, just as they would if they were heading out for a night on the town.
"What I tell girls is pretend that you are coming to a concert, but you are part of the concert," Jones said. "Rihanna, Beyonce, Ciara ... be whoever you want to be. If you ever wished you were that starlet on stage, you are her right now."
Miami has some of the hottest nightclubs in the world, so it's no surprise that the city has inspired some of the latest cardio workouts, and the Vixen Workout has gathered some serious competition. Another dance workout class gaining traction out of Miami, called the 305 Fitness, has a live DJ and describes itself as a night out dancing with girlfriends disguised as a workout.
In the Vixen Workout, Jones works with her backup dancers to create a playlist for each class, mixing up the tracks from Lil Wayne to Jay Z to Beyonce. In the end, participants can burn hundreds of calories for $12 per class.
Christy Rodriguez, 26, from Miami said she has lost 30 pounds since she started the Vixen Workout three months ago and rarely misses a class, no matter where it's taught. She flew 1,000 miles to take the class with Jones in Brooklyn.
"They want women to reach their maximum potential and then for them to make more goals and continue on, and not just in working out and losing weight and whatever, but in your life," Rodriguez said.
A few moms said the class was an escape from the daily grind of going to work and being at home with the kids, and was a chance for them to let their hair down.
Edrey Greene, a mother of two from Brooklyn, said she started taking the class to finally shed her baby weight. She said she preferred the Vixen Workout over the gym because it gave her a sense of a "team effort."
Greene said her two daughters find her going to the Vixen Workout "interesting."
"They are like, 'Mommy, what are you learning in this class?' They've seen pictures and they're like, 'What position is that?' so they're like, you know, 'a little shocking,' but they understand Mommy is just trying to get her workout in," Greene said, laughing. "It's just for me, and I just really enjoy it."
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