Not all those sold on the virtues of human vibration are plugging in to shake. Bones for Life, an alternative exercise therapy aimed at reducing risk for osteoporosis, teaches self-generated vibration. The therapy is an adjunct of Feldenkrais, an exercise method developed by Russian-born physicist, engineer and judo instructor Moshe Feldenkrais, for developing body awareness through gentle movement. The Feldenkrais method aims to help improve posture, flexibility and coordination, while relieving pain and speeding recovery from injury.

Bones for Life creator Ruthy Alon, an Israeli Feldenkrais practitioner, expanded on that work by devising a series of springy and rhythmic movements to shake the body. The method, taught in the United States since 1997, results from research suggesting that vibration can build bone mass.

"The difference is that we believe you can do it for yourself; that you don't necessarily need a machine," said Dianne Fecteau, a practitioner with the Feldenkrais Center of D.C. who teaches a Bones for Life workshop.

In one typical movement, participants stand erect, with shoulders relaxed and knees slightly bent, and gently bounce by lifting and lowering the heels. They also perform pelvic taps by lying on the back with knees bent, and gently bumping the pelvis on the floor. Fecteau says that people who do the movements will feel the vibration through their bodies. Fecteau's recent eight-week Bones for Life workshop, which cost $135 for eight classes, attracted mostly women in the 40-plus set.

Brenda Beeland, a 38-year-old Washington-area resident who suffers from chronic lower back pain, tried a workshop and an all-day session. The sessions, she said, made her more conscious of how she walks, holds her head and reaches with her body.

Hedy Ohringer, who teaches a five-lesson series for $45 at the Friendship Heights Community Center, says one of her students, a man in his mid-60s, credits the classes with loosening his calves and eliminating his lower back pain.

So far, there are no peer-reviewed studies that evaluate the effectiveness of Bones for Life, either alone or compared with electronic whole-body vibration. On the other hand, notes Beeland, it's a seemingly risk-free way to get the body moving. And that's important for people with back pain, Beeland noted.

"You're so afraid that you're going to do something that's going to flare up the pain that you stop moving, and that's probably the worst thing you can do," she said.

Resources:

* Bones For Life, www.bonesforlife.com. The Web site has a state-by-state instructor locator.

* Feldenkrais Center of D.C., www.feldyusa.com; phone 202-237-0072.

-- Karen Pallarito