New Thinking on Which Exercises Build Bone

It used to be thought that any exercise at all would be good for you, and build bone. But now, it turns out only a few very specific types of exercises actually increase the density of our bones.

A very recent study published in the Journal of the American Medical Association looked at hip fracture among the elderly and how quickly they died after it. The New York Times Health Section reports the study results were that the 12-month mortality rate associated with the injury is slightly over 20 percent. That means a year after fracturing a hip, about one in five people over age 65 die. Add to this a series of articles put out this month in the journal of the American College of Sports Medicine which pointed out an ongoing controversy in the field of sports science about how exercise works to increase bone strength, or doesn't. What these articles were discussing were some unexpected findings. One, that showed that competitive swimmers had lower-then-anticipated bone density. Also, that some competitive cyclists had fragile bones. And finally, that weight lifting did not strengthen bones much at all. Researchers are the first ones to admit that they don't really understand this. What it comes down to is they are beginning to think that in order for bone mass to increase, it needs a large signal released in a relatively big burst. So, what kind of exercise comes under that umbrella? Researchers say brisk walking has been found to stimulate bone density in older women, but that it must be at a very fast pace. The best exercise that they have found for building bone is jumping up and down, for as long as you can, or as long as the downstairs neighbors can take it. Dr. Daniel W. Barry, an assistant professor of medicine at the University of Colorado, at Denver, and a researcher who has studied the bones of the elderly and of athletes is currently conducting a study to find out whether supplementing competitive cyclists with calcium chews before and after exercise will reduce the bone-thinning response that is usual with that exercise. He expects the results to be out in about a year. Studies in Japan, have shown that mice who jumped up and landed 40 times in a week increased their bone density quite a bit after 24 weeks. The mice were able to maintain that density by hopping up and down only about 20 or 30 times every week after that.