“Jiggle” machines to lose weight—those belts that vibrate around your middle while you just stand there—go back to the 19th century.

News flash: They don’t work too well…for weight loss, that is. The best that can be said is that they may help with weight loss…if you also cut calories. Thanks a lot.

But a new generation of “whole-body vibration” (WBV) machines is showing up in some gyms, in physical therapy clinics and even as home fitness equipment. What gives? It turns out that new research is uncovering other health benefits. They help build muscle, and there is some evidence that they may help build bone, too.

The latest benefit—lowering elevated blood pressure.

To learn more, we spoke to Arturo Figueroa, MD, PhD, associate professor of exercise physiology at Florida State University in Tallahassee who has been researching these new machines.

KEEPING YOUR ARTERIES FLEXIBLE

In his research, Dr. Figueroa has shown that 30-to-40-minute sessions three times a week with WBV brought down blood pressure by an average of 12 mmHg systolic and 6 mmHg diastolic over a three-month period.

That’s enough to bring you down an entire blood pressure category. That is, if you are “prehypertensive” (aka “borderline”), with a reading between 120/80 and 139/89, WBV treatment could bring you into the “normal” category—below 120/80. If you are hypertensive, with a reading of 140/90 or higher, you could drop down to prehypertensive—and you might no longer require medication. Dr. Figueroa’s research has been on women after menopause, when risk for high blood pressure increases, but he believes that the blood pressure–lowering effects are likely to apply to older men as well.

How does jiggling work therapeutically? WBV has been shown to make the arteries more flexible—less stiff—Dr. Figueroa said. “Arterial stiffness is a process in which the arteries lose their elasticity,” he explains. “A stiffer artery makes the heart work harder, raising blood pressure and cardiovascular risk.” WBV may make arteries—including the peripheral ones that go throughout the body—more flexible by improving the functioning of their lining cells (the endothelium) and by stimulating production of nitric oxide, which helps arteries contract and dilate more efficiently.

READY TO RUMBLE?

To put this research into perspective, remember that regular exercise also reliably lowers high blood pressure, although not as dramatically. Exercise with WBV is no substitute for aerobic exercise and strength training, which have many more benefits for the body and the mind than can be expected from WBV. Indeed, these machines often are used in physical therapy clinics for people who can’t do conventional exercise, such as someone recovering from a stroke or with severe arthritis.

Want to add WBV to your exercise routine? First, if you’re being treated for hypertension or other ailments, get an OK from your doctor—and don’t stop taking any medications without his or her approval. Next, try out one of these machines at a gym or physical therapy clinic that has one—especially before sinking hundreds or thousands of dollars into buying one for home use.

Be aware of possible side effects. As with any exercise, you can experience fatigue and muscle soreness. You may also experience skin redness and itching during the initial sessions due to the increased blood flow to your legs. These are minor. Swelling (edema) in the legs also can happen, but it is rare—if you experience this, tell your doctor.

The most important advice: Whether you use a WBV machine at a gym or get one for home use, Dr. Figueroa advised that you’ll get the most benefit if you first get trained by someone who knows how to work with WBV, such as an exercise physiologist. In fact, he said, gyms that have these machines often stick them in an out-of-the-way room because no one knows how to use them properly. “There are many personal trainers who are not prepared to provide advice for WBV training,” warns Dr. Figueroa. “Personally I have seen physical therapists use them with patients who wear shoes during the vibration exercise. That dampens the beneficial effects, negating some of the benefits.” There are other subtleties such as how to bend your knees to get the best benefit, but they’re easy to learn from a trained instructor the first time you use one of these machines.