TOM REESE
	At Curves for Women in Leschi, signs of lost weight, fat and inches hang from the ceiling.

A rather tricky question, as I discovered.

At a time when many health professionals are concerned about trends toward sedentary lives, the Curves for Women chain of fitness clubs seems to be getting many women moving, with promises of being fast, fun, safe, easy, comfortable, convenient, effective and affordable.

Yet some of the very features promoted by the clubs might be considered drawbacks.

Curves features a 30-minute workout based on circuit training, which combines resistance and cardiovascular exercises. Each small club has 16 stations, alternating hydraulic-piston strength-training machines with cushioned wooden aerobic recovery platforms. A member can begin her workout at any location, at any time. She exercises at each station for 35 seconds, moving on and checking her heart rate when cued by a taped voice.

Such workouts have many benefits, according to the folks at Curves. To examine a few key claims, I sought help from Kathryn Russell, instructor for the Health and Fitness Technologist program at Renton Technical College.

• Curves says users burn up to 500 calories in 30 minutes.

Russell says reliable and recent research on calories burned during circuit training estimates closer to 300 calories — for a 175-pound person.

• On an anonymous visit to one club, I was told Curves users burn more fat than with other workouts by getting into a "fat-burning range" (60 to 75 percent of one's estimated maximum heart rate) on the resistance machine, and keeping it there on the aerobic platforms.

Russell says while it's true we may burn a greater percentage of fat in that range, calories are burned in a much wider range. A more significant number for losing fat is total calories burned vs. total calories consumed, she says, and higher-intensity and longer exercise can burn more calories.

• The hydraulic resistance machines "offer a symmetrical workout by simultaneously working opposing muscle groups," Curves says.

Hydraulic machines, also known as isokinetic machines, offer "concentric" training, in which the muscle shortens, as it does when lifting a weight. But "eccentric" training, when the muscle lengthens, as when resisting a weight on the way down, is important in maximizing gains in lean tissue and strength, Russell says. She adds that the direction in fitness today is away from limited machines and more toward "functional" training that incorporates not only both directions and a wide range of motion but also balance and coordination.

Because the body adapts to stress, all exercisers need to change their programs regularly to continue to see progress. Russell is concerned that women might go to Curves, not achieve the results they seek, "and then feel that exercise itself isn't successful for them."

Despite all that, I have qualms about dissing or dismissing Curves for Women.

I called back the woman who'd left that phone message. Teresa Rich-Mackenzie, 56, a social-services supervisor for the state, joined the Northgate Curves June 1. She has worked out there three times a week since. "I haven't missed once."

Rich-Mackenzie finds the environment nonthreatening and even inspiring, when she sees very large or shy women who might never go to a more conventional fitness club.

She has noticed differences in her body: "I haven't lost but a few pounds, but I've lost a couple of percentage points of fat. I know I'm stronger. I can see some definition. I know my endurance is better." Plus: "I sleep better. I have more energy. I'm nicer to my family. My stress level is better.

"The fact is, I like to go."

If that were true of more of us, whatever form of regular exercise we choose, all those health professionals might not have so much to worry about.

For more information: www.curvesforwomen.com or 800-848-1096.

Molly Martin is assistant editor of Pacific Northwest magazine. She can be reached at 206-464-8243, mmartin@seattletimes.com or P.O. Box 70, Seattle, WA 98111.

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