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Aug. 8, 2001 -- A new study is giving out good vibrations.
The study, in this week's Nature, suggests that gentle vibration can improve bone growth. If the findings hold up in humans, they suggest a new way to prevent osteoporosis, or bone loss often seen in menopause, without drugs.
"Exercise may prevent osteoporosis, but we always thought it had to be short bursts of intense activity," researcher Clinton Rubin, PhD, tells WebMD. "Our work now shows that even very low levels of mechanical stimulation promote bone growth."
Without the force of gravity pulling on the skeleton, astronauts lose bone at the rate of 0.2% per month, Rubin explains. Conversely, a professional tennis player may have 30% more bone on his playing arm.
"The skeleton is a smart material accommodating the demands placed on it," says Rubin, a professor and chair of biomedical engineering and director of the Center for Biotechnology at SUNY Stony Brook. "Unfortunately, most of us tend to sit around too much, so bones get weaker."
In his study, adult female sheep treated with gentle vibration to their hind legs for 20 minutes daily had 30% more bone in their legs than did untreated animals after one year.
"This is very exciting, as it suggests ways to treat bone loss without drugs," says Robert Marcus, MD, a professor of medicine at Stanford University who reviewed the study for WebMD.
"Although there are FDA-approved drugs to prevent bone loss in menopause, most women probably don't want to take a drug every day for 40 years," Rubin says.
Or in some cases, the women can't take the drugs. Such is the case with two patients in Bangor, Maine followed by Cliff Rosen, MD, president of the American Society of Bone and Mineral Research. Because of other medical problems, they are unable to take any drugs or do any exercise for their severe osteoporosis, but seem to be responding to gentle mechanical stimulation.
"We're very excited about this approach, which could be an alternative or even a mainstream therapy," Rosen tells WebMD.
With his co-workers, Rubin is already testing the effects of gentle vibration on bone loss in 64 postmenopausal women. Half of them stand on a vibrating platform resembling a bathroom scale for 20 minutes daily, five days weekly, while the other half stand on a similar device that does not vibrate. The forces involved are so gentle that the women can't tell whether or not the platform is vibrating. Rubin says it's still too early to be sure how his study is turning out, but calls it "very encouraging."
"The absolute worst thing you can do to the skeleton is to put it to rest," Marcus tells WebMD. "While active people seem to have less risk of brittle bones as they get older, not every woman who goes through the change feels like running a marathon."
"We're trying to trick a 68-year-old skeleton into thinking it's a 23-year-old skeleton," Rubin says.