April 2, 2014 10:38 p.m. ET
BROOKLYN, N.Y.—On a crowded dance floor, a group of 50 women are swaying, stomping, lunging, and gyrating to singer Jason Derulo's "Talk Dirty," Pitbull's "Don't Stop The Party," and other popular numbers blasting over loudspeakers.
It could be any trendy New York club, except here the dirty words and sexually explicit lyrics are missing from the raps, and no men are allowed.
The occasion is a weekly all-female Zumba class geared to a distinctive clientele: Orthodox Jewish women from nearby religious communities. With lives guided by Do's and Don'ts, few of these women are Livin' La Vida Loca—though in class they do at least get to dance to it.
Led by Shimrit Adar, a 31-year-old Israeli-born instructor, the Zumba class has become a popular venue for an especially insular group of women. "These women need an outlet and I have found them an outlet—dance," says Ms. Adar. "It is such a relief."
Her students, who call her "Shimi," couldn't agree more. Every Wednesday night, they make their way discreetly to class, situated in a synagogue basement. Stepping out of their traditional ankle-length skirts and long-sleeved blouses, they don typical exercise gear—stretch pants and tank-tops or T-shirts. Many let their hair down, literally, by removing hats or wigs.
"Zumba is my therapy," says Sara Ovitsh, a devotee of the class. "It is my one hour of running away from life, of escaping from my reality." Ms. Ovitsh, a mother of four who works as a lactation consultant, adds: "I either go to a psychiatrist or I go to Zumba."
It is also a lot cheaper than therapy at $12 a class.
But Ms. Adar's class, as well as Zumba courses in other religious Jewish enclaves, have come under scrutiny by rabbis concerned about the suggestive moves and music—and who fear the popular dance-exercise class violates hallowed principles of modesty. Echoing the fears that have greeted hip-shaking pop-culture trends since Elvis Presley, some rabbis say Zumba's music and moves could be morally corrupting.
Zumba, with a mélange of fast-paced music—from hip-hop and rap to Latin and Bollywood—has attracted millions of participants. Zumba classes provide "confidence and happiness and a sense of community," says a spokeswoman for Zumba Fitness, the Hallandale, Fla., company that devised Zumba and owns the trademark.
Ms. Adar, who is Orthodox and a mother of four, says she works hard to produce a "kosher" Zumba, toning down the friskier dance moves and producing a special version for younger girls using only Jewish music ("Jewmba"). Finally, she has enlisted her husband, Daniel, to sanitize salty tunes.
Mr. Adar says editing a single tune can take hours. Working with a friend and Zumba class devotee, Rebecca Wasserstrum, they will either change suggestive words or delete them. To date, they have sanitized nearly 50 songs.
For example, in "Talk Dirty," Mr. Derulo keeps repeating the line "talk dirty to me." Using special software, Mr. Adar changed the lyric to "talk jazzy to me." A lyric in the song about forming a menage-a-trois—"We could menage-a-three-oh"—became "We can make a friend in Rio."
Forget words such as "booty," "naked" or even "sexy," that crop up in popular songs—they immediately are taken out. Even Ricky Martin's "Livin' La Vida Loca" was subjected to the Adars' digital scalpel. The verse "She'll make you take your clothes off," was replaced by "She never drinks the water."
The system can still fail. Every once in a while, someone presses the wrong button and the original version of a song blares, complete with four-letter words and suggestive lines. No matter—several of the women say they don't even pay attention to the lyrics.
"There is a cultural war going on—the more permissive general society gets, the more the religious community becomes insular," says Zev Brenner, a radio talk show host whose program, "Talk Line" caters to Jewish listeners.
Zumba, he believes, has brought out the rabbis' greatest fears, including concerns about listening to secular music. "It is not only the music—it is the moves, the fact that women are dancing to this provocative music, and dancing in what is perceived as an immodest way," says Mr. Brenner, who has aired two shows on the kerfuffle.
In Lakewood, N.J., home to a large Orthodox community, The Gym, a popular facility, decided to eliminate Zumba from its roster though it was well-attended, according to chief operating officer Joshua Novoseller. Hearing that some community members were "uncomfortable," he says he made a "business decision" to cancel Zumba. Practically overnight he lost 200 members, he recalls. But in the weeks that followed, he says 400 people joined.
Rabbi Eliyahu Fink of Los Angeles, an Orthodox rabbi and blogger, says of those who object: "The objection is that this kind of dance is too sexual." That said, Rabbi Fink adds, "The rabbis who are banning Zumba don't do Zumba and they certainly don't watch women doing Zumba."
What came to be known as Zumba was created in Colombia and transplanted to Miami in the 1990s. Raquel Perlman, mother of the company's CEO and co-founder, says she brought the idea to her son's attention, so smitten was she with a fast-paced dance-exercise class in her Florida condo. "All women should be able to enjoy Zumba," Mrs. Perlman says. "Even if some songs need to be edited or even banned."
Chana Rivka Flaum, a 41-year-old homemaker and mother who takes Ms. Adar's class, says that far from being led astray because of Zumba, she became a Torah partner with another classmate, and they now study together.
"We lead very stressful lives and we don't have other outlets," says Nikky Admon, another Orthodox classmate. "There are no clubs," she says. This is the only quote unquote 'kosher' outlet women have."
Ms. Ovitsh, her classmate, shrugs off the controversy: "It is an exercise program—HELLO…"
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