The schmaltzy strains of "Moon River" flow from the speakers as couples start to waltz in a studio in Santa Monica, Calif. Under a mirrored ball, they glide across the hardwood floor with perfect posture, silently mouthing the rhythm: one, two, three; one, two, three.
The scene's different over the hill in Los Angeles' San Fernando Valley. Twenty women, mostly clad in black workout pants and sneakers, sweat profusely to a spirited jive step as "Proud Mary" blasts and their teacher screams, "I need attitude!"
Both classes are part of a full-tilt revival of ballroom dance. Otherwise closeted dancers are finding themselves attempting a waltz, fox trot, cha-cha or tango. Thanks in part to the popularity of shows such as Dancing With the Stars, ballroom has gone from stodgy and unhip to cool.
Dance studios are experiencing a steep uptick in the demand for classes. And somewhere between a box step and a crossover turn, people are discovering that ballroom offers a great, less-tedious workout.
"The idea that you have to go to the gym and get on the stair climber or take an aerobics class is silly," says John Jakicic, chairman of the department of health and physical activity at the University of Pittsburgh. "There is some evidence that almost any kind of dancing has a very high-energy expenditure to it, and the activity is continuous for at least minutes at a time, so there are cardiorespiratory changes going on."
Dance has a built-in social factor, too. Being accountable to a dance partner or friends who expect to see you in class is a great motivator for sticking with it.
And it's fun - which is more than most people can say about their last spin on the elliptical trainer. "You're more likely to do it," Jakicic says.
The amount of calories burned varies. Half an hour of slow dance, such as a fox trot, burns about 102 calories for a 150-pound person, according to the Web site CaloriesPerHour.com. A faster step, such as salsa, can hit 255 calories. "The more you can get the whole body shaking, the better off you'll be," Jakicic says.
Dance works postural muscles in the back and abdomen, and because legs are moving constantly, they should get toned as well. (Still, Jakicic adds, if you're only dancing a couple of times a week, "you need to do stuff on other days - take a walk outside.")
Two studies have reported that ballroom dance, on the elite level, is an intense workout. In one, published in a 2002 supplement of the journal Medicine & Science in Sports & Exercise, Danish researchers tested elite amateur ballroom dancers' heart rates and blood lactate levels. The physical demand was considerable, and dancers achieved high levels of aerobic and anaerobic activity. (Latin dances scored highest.)
Exertion is likely to be less intense for beginners. Still, one doesn't have to be Maksim Chmerkovskiy or Karina Smirnoff to experience the benefits of ballroom.
John Cassese, who owns the Dance Doctor studio in Santa Monica, says newcomers are often surprised at the calories burned: "They say to me, `Wow, this is a workout, and we've only had one lesson.'"
All that gliding may look effortless, but it's definitely work, even at the beginner level, Cassese says. Upright posture (in ballroom parlance, "dance position") is a must for looking elegant and confident. During class, spotting some slumping shoulders, he stops in the middle of explaining a step and asks students to walk to the wall.
"Stand with your feet against the floor, your calves, buttocks and head against the wall," he says. "Now walk away from the wall in dance position to your partner." The class obeys - and suddenly everyone's standing straight, stomachs tucked in, shoulders back, chins up. The most slouchy person in class instantly looks like Fred Astaire.
Jerry Jordan, co-owner of Atomic Ballroom in Irvine, Calif., says that Dancing With the Stars, as well as other dance shows and movies about ballroom, have made these forms of dance part of the U.S. culture. "The stereotype that it's just for ladies is gone," he says, "as is the notion that you have to train for years and years. It's for everybody." That includes macho guys, thanks to sports stars such as former football player Emmitt Smith and boxer Floyd Mayweather taking a turn on the dance floor.
A class titled cardio ballroom, taught by former Dancing With the Stars dancer Louis van Amstel, offers especially intense dance workouts. Van Amstel and actress Lisa Rinna, his dance partner on the show, came up with the concept - it's structured like an aerobics class, no partners needed. It begins with a warm-up, then segues into basic salsa, cha-cha and jive steps, progressively adding variations, all to speaker-busting levels of Mariah Carey, Gwen Stefani and Cher.
"We realized that ballroom works on a fitness level," van Amstel says after a recent class at Anisa's School of Dance in the San Fernando Valley, his shirt and pants soaked with sweat. "It's the best way to make people lose weight because you're not really here for a fitness class, you're here to dance."
Jeannine Stein writes for the Los Angeles Times.