A July 4 session of Z-GoGo, which adopts a Zumba-like workout to go-go, D.C.’s quintessential musical genre. The affordable classes typically draw 100 students. (Go-Go Fitness)

“Werk. Werk. Werk.”

The mantra echoes throughout the Panorama Room at Our Lady of Perpetual Help Church in Southeast Washington. It’s the Fourth of July, and the atmosphere is appropriately festive. Danette “Dani” Tucker is onstage with a group of dancers. And when she says “werk, werk,” (a playful call for the dancers to put some personality behind their steps) she wants to hear you repeat it.

“I will start this over,” she says with a grin.

It feels a bit like a pep rally, but make no mistake: This “werk” is really work. On the floor, arms are in the air, knees reach higher and higher. The unmistakable beat of go-go music reverberates through the room.

This is Z-GoGo. The Z is a nod to Zumba, a dance workout generally choreographed to Latin music. But instead of dancing to the Latin rhythms, students across the region are working out to the music they grew up on. They describe Z-GoGo as a fun, high-energy way to shed extra pounds.

“I love go-go music, so this was something that was really special for me,” says Titania Benton-Ellis, a Z-GoGo devotee who grew up in Alexandria.

Z-GoGo was founded by Tucker, Erica Berry and Tricia Barnes, all native Washingtonians. Tucker had been teaching traditional Zumba classes and decided to test out a new routine — one choreographed exclusively to go-go — for eight students in a small Anacostia dance studio. Her students were hooked.

That was in February of last year. Today, classes are taught in locations across the Washington area. D.C. expats have even started classes in Washington state. And there are Z-GoGo offshoots — a low-impact class for workout novices and a “Z-Gospel” workout set to gospel tunes.

Class sizes vary, but instructors say a typical class, like the one held on a recent Monday night at Iverson Mall in Hillcrest Heights, can draw more than 100 people. A lead instructor and a fitness team — several Z-GoGo enthusiasts trained to hype up attendees — demonstrate the moves. The format mirrors the call-and-response vocals found in go-go music.

Kelli Anderson, a 33-year-old mother of twins from Southeast, is a friendly face at Iverson and other Z-GoGo classes, where she’s known to yell out encouraging phrases to attendees. (“There’s nothing wrong with making it sexy,” she says with a laugh while demonstrating an ab-clinching body roll.) She’s been doing Z-GoGo for about nine months and says she’s lost more than 20 pounds.

Vivian Boykins is the main instructor at Iverson, where classes are held three times a week. She had been doing Zumba when a friend suggested they go to a new class choreographed to go-go.

That’s how a lot of attendees hear about the class. “This is all word-of-mouth,” Tucker says. Z-GoGo promotes its programs on its Web site and Facebook, but she says the organizers have never paid for advertising because they want to keep the price of each class low at $5. Students can also buy a $20 pass for five classes.

The majority of students are working and middle class, Tucker says, and the group finds other ways to keep costs down, offering free classes to children 15 and younger so they can work out alongside their moms.

“We want mothers to work out with their kids, and we want them to develop those healthy habits with their kids,” Tucker says.

Like many Z-GoGo instructors, Boykins took the class for several months and decided to pursue certification as a Zumba instructor. Tucker said Z-GoGo instructors are licensed to teach Zumba. But the classes aren’t technically considered Zumba because those require a certain ratio of Latin music. Tucker and Berry own Go-Go Fitness and are in the process of trademarking their fitness program.

At holiday classes, like the one held on July 4, Z-GoGo classes converge and participate in a dance battle for prizes. Some sported black tanks with Z-GoGo written out in rhinestones. Others wore jerseys or decorated T-shirts to represent their class locations.

Tamara Rutland started attending Z-GoGo classes recently with a group of her sorority sisters, who wore purple and black ensembles to the holiday class. “We liked the energy,” says Rutland, adding, “It’s nice to have a group of mostly women encouraging one another, supporting one another.”

Z-GoGo has its fair share of male students. Rutland’s instructor is NeuNeu Cade, whose chiseled abs and energy are a testament to the program’s fitness potential. He grabbed attention at his first class in February. “Everyone was talking about the guy in the back,” said Cade, who had experience teaching Zumba.

Kip Coleman, a D.C. police officer, would have been working out alongside attendees at the July 4 class, but he was facing a 12-hour shift. Coleman admits he was initially hesitant about taking the class. But Z-GoGo has helped him stick to a cardio regimen, one he recommends to the recruits he teaches at the D.C. police academy. “I’m committed to it,” he said.

Coleman was in uniform as students from the class held at Forestville’s Flair Health & Fitness club staged a crime-scene-themed performance, complete with police tape that garnered laughs from the crowd. Working in the community is an important aspect of Z-GoGo, particularly since go-go has a “bad rap,” as Tucker puts it, the result of violence seen at some go-go performances.

It’s no coincidence that bandleader Chuck Brown, who died last year, has a resounding presence in all things Z-GoGo. The company sells two workout DVDs featuring Brown’s music, the second of which is dedicated to the “Godfather of Go-Go.” Tucker says the group aims to channel his positive vision of go-go music.

The group from Flair took top honors in the July 4 dance battle, followed by Iverson in second place. Their instructor, Boykins, wasn’t there to see their win. She was at a family reunion in Mississippi where, she said, she planned to teach a Z-GoGo routine.

Z-GoGo offers classes most weekdays and Saturdays. Check gogofitnessllc.com to find a class near you.