Lisa Welch stares herself down in the mirror. Hips out, head back, her knee-high leather platforms clicking on the hardwood floor to a musical beat, she sensually exaggerates her walk toward the floor-to-ceiling steel pole. Welch bounds skyward, catches the pole then–slowly, methodically, sexily–descends.

Welch is not, nor has she ever been, a stripper. She’s a personal trainer and fitness class instructor, and she’s reviewing her latest curriculum: pole dancing.

Welch “approached me and really wanted to do this,” says Heather Dupuis, owner of Vie, where the classes have been offered since September. “At first I was hesitant,” admits Dupuis. “To buy the poles, we’re talking a couple thousand dollars. But she was confident she could fill it up.”

Fill it up she has. At first, Welch taught an introductory class one night a week. By January, Vie had classes four nights a week and was turning people away. Demand is still on the rise, so Dupuis will bring on another instructor for the next six-week session starting in September.

Jen Burt, Nikki Raymor, and a professor who asked to remain anonymous convene at Vie for a class. They all move confidently in their knee-high leathers, short shorts, and tight tanks. Welch recommends the attire not only for functionality–bare arms and leather boots help grip the pole–but also because looking and feeling sexy is one of the purposes of the class. Of course, it’s not the only purpose.

“You leave the first class laughing and smiling,” says Raymor. “After the second class, I wanted to vomit” because of the physical demands. Welch says no one has ever quit, but it’s an intense workout: “It takes a lot of strength to hold your own body weight up while twirling around a pole, climbing it, or hanging upside down on it.”

Though Welch says a man wouldn’t be turned away, so far all her students have been women. To her knowledge, none has taken the class at the request of a spouse or boyfriend, though several have confided they’re doing it as “gift” to a partner. But the obvious beneficiaries are the women themselves: Raymor, thirty-seven and a mother of two, Burt (thirty-five), Welch (forty-three), and the anonymous prof (forty-four) all look ten years younger.

A taxing workout for the upper body, core, and lungs, the class is as much about boosting self-confidence as shrinking waistlines. “There’s a psychological and a physical piece that go into it, and [Welch] is just really good with it,” says Dupuis. “She wants you to feel really comfortable with your body, feel sexy, and not be ashamed of being sexy.”

Freep.com recently published a story about residents of Orion Township trying to shut down a pole-dancing studio because they considered the classes indecent. But Vie’s had no such complaints. “It’s not exhibitionist,” says the professor. “There’s no audience. You keep your clothes on. The mirror is the audience.”

“It’s pretty much gymnastics, but when you break it down, it’s pretty much strippers, so there’s a certain amount of intrigue,” says Welch. “People who come in and see it as taboo and intriguing and don’t look at themselves that way, those are the people that really transform in this class, and that’s why I like to teach it.”