Men's Osteoporosis Support GroupYoga for osteoporosis Topics in Geriatric Rehabilitation, 25;3;244-250. Yoga for Osteoporosis: A Pilot Study. Fishman, LM. This study involved 10 postmenopausal women and one 74-year-old male, average age of 68 years, who did 10 yoga poses per day for 20 to 30 seconds per pose for two years. They were compared to controls who did no yoga. The results showed, "Yoga practitioners gained 0.76 and 0.93 points for spine and hips, respectively, on the t scale when compared to controls (P = .01). There were no injuries. The author concluded, "Yoga appears to be an effective way to build bone mineral density after menopause." Editor's comments. If these results hold up through other well controlled randomized clinical trials, this would be exciting, if not incredible. Imagine just a few minutes a day of minimal exercise to have large increases in bone mineral density (BMD). I hope this happens, but don't think we can assume that will happen quite yet based solely upon this study's results. And I have multiple issues with this study and its results that I want to cover here. Exercise time. If someone is holding a pose for 20 seconds and doing 10 poses that is four minutes of actual exercise time per day. If it is 30 seconds, that would be six minutes per day. To increase someone's BMD by almost 10% (figuring that one full standard deviation in T-score is approximately 10%), would be phenomenal--simply amazing. If yoga is this effective I would find it hard to believe that no one has noted that yoga practitioners who do routines that are much longer than four to six minutes per day of pose time consistently have normal or above normal BMD, which I would expect to occur. The author notes that the materials and methods involved lab work, including urine NTX, a biochemical marker test to show the level of active bone resorption. However, I didn't see the results of that test anywhere. That would be important as it could confirm the other results. Additionally, a pilot study that included the urine NTX results for multiple times per pose or multiple numbers of poses would have been very interesting. For instance, would four minutes just holding a single pose, or perhaps two poses, have been equally as effective? Would holding each of the 10 poses for 60 seconds have been twice as effective? Urine NTX might have been suggestive and helped to provide information on how best to perform the next clinical trial. I hope future trials include urine NTX test results. Weight bearing exercise. This is generally held as the gold standard to gain BMD for all individuals, postmenopausal, male or female, or whatever. Weight, working against gravity, is what appears important to stimulate bone growth. Fishman cites studies done on turkey wings in 1984 that showed that bone growth could be stimulated by "unusual pulls," or what the authors of that study called "a suitable dynamic strain regimen." What exactly causes the dynamic strain? One, for instance, would think that cyclists who use incredible amounts of muscle stress and strain in their sport would benefit by increased BMD if strain is important, but that is not the case. What is it about yoga that would allow increases in BMD without the exercise being weight-bearing? That needs to be shown in future studies to make these results tenable. Study conduct. Was this actually timed by the participants or anyone else? Could they have actually exercised for two, three or more times the amount suggested? Or possibly for less time? How can we know? How can we determine compliance without overseers actually verifying time in each pose? It was stated that people who went below 30% compliance were contacted. Were people in the final group of 11 in the group with compliance below 30%. If so, how many, which ones were, and exactly how good was their compliance? If we don't know how compliant they were we are missing important information. If any had 30% compliance and almost 10% increases in BMD, that is even more incredible than those who were 100% compliant. If only 11 people stayed in the study out of 117, this is a problem. This means fewer than 10% of the participants completed the study. Can we assume these were the highly motivated people? Did they perhaps engage in other BMD-increasing behaviors because of their high motivation? Did they make dietary, other forms of exercise, or other changes that might benefit bone mineralization? Is it something about yoga that causes so many people not to stay with the program? If so, what? If not, what? Some individuals were on osteoporosis medications, those are not singled out in the results. Shouldn't we know which individuals that are listed were on medications and which ones weren't? Also, how long were they on them and what results had they had from them? He says he used the nomogram of people on medications. I don't see evidence of that in Table 1 or Figure 14. These scores are raw T-scores, which, incidentally are labeled as "mean bone mineral density." Bone mineral density is measured in grams/cm2, not T-scores. So the label is in error for the data presented. Summary. There have been very few studies in any way related to improving BMD with yoga. To see them all in PubMed, type in "yoga for osteoporosis" in the query block. With this dearth of information, the Fishman study is all there is on this topic currently. With the questions regarding this study listed above, there is a strong need for Fishman, and many other researchers, to do controlled clinical trials to try to confirm the pilot study's results. Until then, I see no reason not to do yoga, it appears to be a safe and useful exercise. It probably improves the practitioners' balance, prevents falls, and improves the quality of life. If it turns out that it also increases BMD that will be wonderful, but that must be proven by additional good solid research.
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