RENEE MONTAGNE, host:
If you want a laboratory mouse to grow up lean and strong, don't worry about running wheels and weight training. Just put him on a gently vibrating table for 15 minutes a day, and scientists say the results are amazing. Mice aside, you may want to learn about this technique.
NPR's Joe Palca reports it might work for humans as well.
JOE PALCA: Biomedical engineer Clinton Rubin didn't start out intending to make lean mice.
Dr. CLINTON RUBIN (State University of New York): In my scientific heritage I'm more of a bonehead. I study the bone disease osteoporosis, or bone-wasting.
PALCA: But oddly enough, fat and bone are cellular cousins. The same stem cell that's a precursor to bone cells is also a precursor to fat cells. Rubin says scientists have known for a good long while that bones that get a lot of shaking tend to get larger. Tennis players are a perfect example.
Dr. RUBIN: You know, Roger Federer would have 35 percent more bone on his playing arm than his non-playing arm.
PALCA: But Rubin has shown that you don't need a lot of vibrating; a tiny amount will do. The theory for why vibrations affect bone mass is that somehow the stem cells that make bone sense the motion and say, hey, I think I'll turn into bone so I can tolerate all this jiggling. But if that theory is right, Ruben realized something.
Dr. RUBIN: If a precursor cell is deciding to become bone, maybe it isn't becoming fat.
PALCA: So he and his colleagues at the state university of New York and Stony Brook set up a little experiment. He gave two groups of mice identical diets, but one group he put on a gently vibrating platform for 15 minutes a day. Then he measured the body fat of the group that got the daily jiggling.
Ruben: Sure enough, they have 27 percent less fat 15 weeks later.
PALCA: And stronger bones.
Ruben reports his results in the Proceedings of the National Academy of Sciences. As it happens, scientists were about to launch a similar study in humans.
Douglas Kiel is at the Institute for Aging Research at Hebrew Senior Life in Boston. Subjects will get 10 minutes of jiggling a day.
Dr. DOUGLAS KIEL (Hebrew Senior Life) People stand on a platform and since we're enrolling seniors, we also have a little bar to grab onto for safety.
PALCA: Kiel's colleague, Mary Buoxsein, at Beth Israel Deaconess Medical Center in Boston, says the vibrations are quite mild.
Dr. MARY BUOXSEIN (Beth Israel Deaconess Medical Center): You do feel something but you're not being jolted around as if you need to hold on and you might fall off. I mean, it's really a quite minor stimulation.
PALCA: Buoxsein says she and Kiel initially were only hoping the vibrations would improve bone growth. But now they're planning to see of there are any changes in body fat as well. Of course she can't feed her subjects identical diets, so she doesn't have high hopes for seeing a big difference. And it's not as if she's opposed to people getting their vibrations by walking or running or something a little more aerobic.
Dr. BUOXSEIN: But if we had something that was, you know, very simple and you stand on this platform for 15 minutes a day and it may improve your musculoskeletal health as well as cause you to weigh less or have less fat; that's pretty interesting and intriguing.
PALCA: One last thing. The vibrations do not remove fat cells. Clinton Rubin says once fat cells form, they tend to stick around, and vibrating won't get rid of them.
Dr. RUBIN: If you have a fat mouse, in order to get rid of the fat, you need to metabolize it, just as we've all learned. You need to get those mice out running marathons or pumping iron or whatever it is that mice would do to reduce their fat mass.
PALCA: Scientists are pretty clear that those techniques for reducing fat mass will work in humans too.
Joe Palca, NPR News, Washington.