No leering men, no mirrors, and no lycra-clad, Barbie-doll shaped instructors. It’s no wonder women love Curves, the fast-growing national fitness chain whose franchises have begun popping up all over Maine in recent months.

Launched nearly eight years ago by Texas entrepreneur Gary Heavin, the business focuses on women’s fitness, and succeeds – many of its members say – in providing a sensible, healthy way to lose pounds and inches and gain muscle tone and cardiovascular strength.

The chain is approaching 6,000 franchises nationwide and Canada.

Jack Bullock of Northport, an entrepreneur who sold a Camden-based software business a couple of years ago, decided to buy a Curves franchise in Belfast earlier this year.

By law, Curves cannot ban men from joining, Bullock admitted, but the equipment and facilities are designed for women. He said that around the country, where men have joined a franchise, they have often found it did not meet their needs.

Despite (or maybe because of) the lack of male members, Bullock said one in four fitness centers nationally is now a Curves, and 90 percent of the franchises succeed. His own Belfast operation did so well in the first few weeks that he opened franchises in Rockport and Damariscotta. He is opening another Curves in Fairfield this month and a fifth franchise is pending approval from the parent company.

Each business is profitable, Bullock said. But equally important is the fact Curves is offering a service to women by helping them achieve weight-loss and fitness goals, he said.

The Damariscotta business, which opened in early July, already has 400 members. The Belfast franchise, opened April 1, has more than 600 members. And the Rockport Curves, which opened March 15, has 750 members.

The key to the rapid growth, Bullock said, is the simplicity of what Curves offers and delivers. After an initial assessment, which includes weighing and measuring, and a review of a member’s goals, each woman is ready to begin.

Basically, the routine is the same for every woman. A member plans to visit three times a week, and complete a 30-minute workout each time. After some light stretching, members enter the main room containing the “circuit” – a circle containing 16 to 24 stations.

Eight to 12 stations featuring workout machines alternate with a similar number of stations containing platforms on which women bounce in place. Upbeat music cues the women every 30 seconds to change stations.

The workout equipment looks much like conventional weight machines, but instead of being hooked up to slabs of iron, they use hydraulic pistons, which look sort of like automobile shock absorbers. Unlike weight machines, the pistons work muscles in both directions, one set of muscles pushing and a different set pulling.

It’s what Bullock calls a “double positive” workout. It avoids the risk of injury that comes when weights are lowered. “They’ve found that’s where most injuries take place,” he said.

The hydraulic pistons do not require adjustment from user to user. An especially strong woman will encounter more resistance the harder she works the device; a weaker woman will still be able to pump the handles with less effort.

“The harder you pull, the more resistance you get,” Bullock said.

Between workouts on the resistance machines, the women jog in place on the platforms – simple plywood squares on top of foam blocks. This allows the muscles to recover, he explained, while still keeping up heart and breath rates.

The music tape also cues the women at one point to check their pulse rate to be sure it is not too high or low.

“The essence of this 30-minute workout is, it’s the equivalent of, if done correctly, an hour-and-a-half workout,” Bullock said.

Curves doesn’t aim to produce body builder-type physiques, he said. But the workout does return muscle tone.

“You don’t care what the scale says, if you’re going from a size 14 to a 10,” he said. “Plus, they feel great.”

Dr. Nellie Cyr, a professor of kinesiology and physical fitness at the University of Maine, visited a Curves at the request of the Bangor Daily News. Cyr examined the equipment, reviewed the workout and talked with some members.

Cyr was favorably impressed, she said, and was especially struck by the Curves philosophy.

“Their philosophy is unique because it’s based on cooperation and a sense of community,” she said. “This place really fits a new kind of paradigm.”

Traditional gyms are often “a place to show off,” Cyr said. “You wear spandex, you stand and flex.”

Curves, she said, appeals to women because the circle encourages interaction. At the Curves Cyr visited – she wouldn’t say which one in order to maintain the women’s privacy – the members talked about their children, movies, and what they were going to make for dinner that night as they worked out.

Unlike weight machines, the pneumatic resistance machines allow women to avoid any semblance of competition, Cyr said. And yet the devices do deliver the “double-positive” muscle exercise, she said.

Cyr said she also liked the workout because it focuses on movement. Once inactive women begin to work out, they “start to feel good about themselves, start to eat better, and they start to walk a little taller.”

Cyr said she looked for a downside to Curves, but saw only positives.

Curves offers nutritional counseling, and suggests a diet that shuns carbohydrates, like the famed Atkins diet.

“If you come in and do the 30-minute workout three times a week, you will see results,” she said. It’s not uncommon for women to lose 20 pounds without dieting, he said.

The program costs an initial $150 to become a member, and then another $29 to $39 per month depending on the payment plan, Bullock said, adding that specials, such as half-price or two-for-the-price-of-one deals, are often offered so the start-up cost is more typically about $75.

The subsequent monthly rate is $29 with a direct-deposit payment plan and $39 otherwise.

To support the franchise’s value, Bullock displays a notebook containing testimonials from the Belfast Curves.

“I’m one who never exercised,” wrote one woman. “Here, I don’t feel pressured to work harder than my body allows.”

Another wrote that she has been overweight all her life, and remembers being teased as a child. She tried private gyms, but described them as “all macho men and spandex girls.” After two months at Curves, she cried when the manager measured her and it became clear how much she had lost.

“Walking in that door by myself was the one of the hardest things I have ever done,” wrote another woman, “but I think it’s going to be one of the best things I have ever done for myself. I finally found something that I can do and that I like. I find myself actually looking forward to exercising.”