In mid-July, a buff, if bedraggled (has she forgotten the benefits of shampoo?) Madonna appeared on Oprah and shared the secret of her long, lean, chiseled body--an exercise system called Pilates. Initially attracted by the spiritual quality of the exercise, its fantastic results were what got her hooked and what has kept her away from the StairMaster forever. Her announcement heightened a trend ready to break out, and within days anyone who was anyone had booked their first appointment in one of Manhattan's numerous studios. Following in the steps of the celebrity set, trendoids from Malibu to Miami were caught up in Pilates fever.

Like martinis, Prada and the Tibetan freedom struggle, Pilates existed long before the celebrity-induced craze made it en vogue. Pilates (pronounced puh-LAH-teez) dates back to the first World War, when its founder, Joseph H. Pilates, was interned in England and forced to work as a nurse. Using springs and hospital beds, Pilates developed exercise equipment for injured and immobilized soldiers. He later brought the unique design to New York City, where he opened his first studio in 1926. The "Universal Reformer," "Cadillac," "Barrel" and "Wunda Chair," all resembling WWI-era torture devices, grew out of these original apparatus.

Today, the Pilates exercise system remains relatively similar to its founder's original concept. It is designed to lengthen and strengthen muscles, to increase flexibility and to rehabilitate injuries. It targets every woman's post-freshman 15 nemesis--the abdomen, lower back, upper thighs and buttocks. Promised Joseph Pilates, "You will feel better in 10 sessions, look better in 20 sessions, and have a completely new body in 30 sessions."

Julie Sorrentino, an instructor of Pilates-based exercise at Body Balance in New York City, recognizes the healing power of Pilates, but warns that "Its not a miracle cure. It will give you the body you want if you're devoted," she adds. "You have to work at it." She recommends a private Pilates session (ranging from about $38 to 60 each, depending on the studio) two to three times per week. For optimal results, the Pilates workouts should be complemented by regular cardiovascular exercise. So, as FM gossip columnists claim, was Madonna's Pilates coming-out party a bit of a fib?

Yes, argues Sorrentino, also a friend of the Material Girl. She stresses that Madonna, a former dancer and perennial workout fiend known to exercise for up to four hours a day, combines Pilates with jogging, cardiovascular exercise and weight training. Post-baby Pilates mainly helps to bring back those famous abs so prominent on the Blonde Ambition Tour.

Madonna wore cone boobs, and we didn't all do that, so why the sudden interest in Pilates? Sorrentino, who has been involved in Pilates since childhood and has owned her own studio for more than five years, recognizes the interest as a transition of Pilates disciples once being dancers (Martha Graham was an early devotee) to athletes in rehabilitation, celebrities and now even housewives.

"It's a baby boomer type of thing," she explains. "They've been through the aerobic stage, they've been through the jogging and weightlifting stages, and now they're 40. They're aging, and Pilates is perfect for osteoporosis, arthritis and building a great body. It's the long, lean look of a dancer's body that they've wanted all along."

Eva Byrnes, a retired dancer and mother of Maja K. Byrnes '00, agrees. Fifteen years ago, she recognized the sudden improvement of a fellow ballet dancer. The dancer in question shared her secret and sent Byrnes to a Pilates class. She has been a devotee ever since. Not only does she value the look maintained by regular Pilates, but Byrnes emphasizes that it is good for a bad back and gentle enough for her to continue workouts with a broken ankle. As for Madonna's sudden interest, Byrnes muses, "I think she'll get tired of it."

Though Pilates studios and instructors have greatly benefited from the attention focused on the routine in the past few months, problems have also arisen in the industry. As any Ec 10 student knows, with a leap in demand comes a concurrent leap in supply, and the suppliers are in a bit of a quarrel. John Gallagher, a physical therapist and businessman, trademarked the Pilates name, making it more difficult to open an official Pilates studio. Many instructors have navigated this obstacle by opening Pilates-based facilities and choosing to incorporate the ideas of Pilates with modern information on anatomy, physiology and alignment. Sorrentino, who runs her studio by this philosophy, argues that modern knowledge makes for a better program. Publicity has affected the industry in other ways as well. While a recent Vogue article upped Sorrentino's already sizable celebrity clientele, recently found it harder to get appointments at their favorite studios.

Interested in Pilates? Boston, not yet on pitch with the Upper East Side, doesn't exactly offer a plethora of choices. While the antiquated MAC houses only traditional aerobics, Lowell House recently began a weekly yoga class. Yoga, though a floor-based exercise, incorporates much of the same philosophy as Pilates. Instructor Matthew Daniell stresses that regular yoga produces "a stronger, leaner, more flexible body." Local best bets for the real thing are Your Center Pilates Based Exercise and Wellbridge Health and Fitness Center, both located in Cambridge and offering Pilates-based exercise.

Of course, Pilates may just be a trend, and a year from now it will be as passe as step aerobics and kick boxing. And maybe Madonna is a big liar and a closet marathoner. But it's probably worth a try anyway, if only for bragging rights.