"The weight-bearing yoga training had a positive effect on bone by slowing down bone resorption which was a very essential indicator for human health because it reduced the osteoporosis risks in this group of postmenopausal women."
-Phoosuwan, M. et al. "The Effects of Weight Bearing Yoga Training on the Bone Resorption Markers of the Postmenopausal Women" J Med Assoc Thai 2009; 92(Suppl. 5):S102-8"Physical activity is profoundly beneficial to bone health & every study that has looked at this has shown a much lower risk of fracture among people who are physically active."
"This really applies to the bones that are exercised--the bones that are stressed. Walking & other weight-bearing exercise reduce rates of hip fracture--but may not do much for wrist fracture, so we need other exercises for our upper body bones to keep them strong."
--Walter Willett, MD, DrPH, is Chairman of the Department of Nutrition and Frederick John Stare Professor of Epidemiology and Nutrition at Harvard University's School of Public Health--
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I've been wondering for awhile about the connection between yoga & bone-strengthening. Here's why.
- My high school friend Sheila is petite, small-boned, very thin, and osteopenic. She's sees a rheumatology/osteoporosis specialist, takes bone-strengthening meds and yet she still continued to lose bone density. When she switched her exercise routine to include a power-sculpt class & yoga she started to see improvements. She doesn't know if it's because of the yoga or the weights, so she's not about to stop either.
- My college friend Cindy is small-boned, thin, and osteopenic. She sees an endocrinology/osteoporosis specialist, takes bone-strengthening meds, and recently noticed improvements in the bone density of her wrists--while here hip and spine remained stable. She wondered if her more regular attendance at yoga classes could be responsible--and the downward-facing dog pose, in particular.
- My yoga teacher mentioned 3 weeks ago that before she started to practice yoga regularly her bone density scan put her in the osteopenic range. After a few years of regular yoga practice she moved solidly into the normal bone density range.
Is it really possible that a regular yoga practice can improve one's bone density? I decided to see if I could find a yoga/bone strength connection in the medical literature.
Makes sense to my lay-person understanding of bones.
"Bones are similar to muscles. Use muscles, and they become bigger and stronger. Stop using them, and they weaken and atrophy. Like muscles, when bones are used--when they support weight or carry a load (within reason)--they get stronger.
When bones bear weight, they experience strain. Strain produces microscopic weak spots. As those weak spots develop, the bone cells in the vicinity release chemicals that signal the body: Weak spot! Send help!Bone-clearing osteoclasts converge on the problem area and dissolve the weakened bone. Then osteoblasts migrate from nearby bone marrow, enter the tiny breach, and create new bone.
Normal strain stimulates the creation of new, strong robust bone. In other words: weight-bearing activities give bones a reason to thrive.
--Amy Lanou, PhD & Michael Castleman, Building Bone Vitality. NY:McGraw-Hill, 2009. pgs. 154-155.--
Full Disclosure: Lanou & Castleman are huge advocates of walking outdoors--up & down hills, or up & down stairs, or carrying a load--as a dynamic bone-strengthening exercise. Dr. Walter Willett is also a big fan of walking for bone health--but he says it strengthens the hip primarily, and we need to stress all the bones in the body. That's where yoga enters the picture.
Searching the Medical Literature for the Yoga/Bone Strengthening Connection
As crazy as it sounds there is next to nothing written on this subject. But, I did come across one well-constructed preliminary report published in 2009 in the Journal of the Medical Association of Thailand, of all places. Click here for the article
Before writing this post, I went back to PubMed and bingo, there's a brand new pre-publication article--hot-off-the-press, called, "Yoga might be an alternative training for the quality of life and balance in postmenopausal osteoporosis," Tuzun, S. et al, European Journal of Physical and Rehabilitation Medicine. Click here to read the full article.
If you are reading this post you will probably be one of the few people in the country who will have heard about this article. The Journal of the Medical Association of Thailand can be found in only 12 libraries in the U.S. With over 5000 medical journals currently competing for attention the odds are slim that this preliminary report will get much notice by anyone.
The Cliff Notes on the Thailand Study
What happens to the bones of women once estrogen walks out of their lives? Bone resorption begins, and new bone formation decreases. And we all know what that means.
Knowing that weight-bearing exercises like jogging, walking, and aerobic dancing benefit bone, the author's of this study set out to see if 5 yoga poses would have a similar positive effect.
- Tree Pose
- Downward Facing Dog Pose
- Warrior III Pose
- Triangle Pose
- Half Moon Pose
Who was in the study: 33 healthy, postmenopausal women, between the ages of 50-60 years old. None of them smoked, drank alcohol, used hormone replacement therapy, or drank more than 2 cups of coffee a day. No one exercised more than twice a week. No one had osteoporosis, or a bone mineral density of -2.5
Who did what in the study: 19 women chose to take the weight-bearing yoga training class. 14 women preferred to join the control group, and just continue with their "normal lives."
The Before & After Tests: Everyone had a blood tests to measure measure their biochemical bone markers. This included the Beta-CrossLaps Test, which measures bone resorption and is used to monitor antiresorptive therapies (eg, bisphosphonates (click here to learn more), and the P1NP Test, which measures bone formation markers. Quality of life was also measured with the SF-36 questionnaire, but that isn't my interest here.
The yoga routine for the study: 10 minutes of stretching before and after yoga, to prevent injury. The group practiced for 50 minutes, 3 times a week, for 12 weeks. They performed 3 sets of 6 yoga poses.
This description seems unclear to me, since the authors only discuss 5 poses--but that's how it's written up in the article.
The Results: After 12 weeks the bone resorption markers (Beta-CrossLaps) of the control group & the yoga group were significantly different (p = .0003). More importantly, the bone resorption marker of the yoga group was significantly reduced by -26.939% from when they started, compared to the control group's reduction of only -0.77.1% That means, the markers for bone loss of the yogis was significantly reduced and those yoga poses were clearly having a positive effect on the control group's bones.
What does the improvement in the yoga group mean? It implies that weight-bearing yoga training could reduce the rate of bone loss in postmenopausal women, and decrease the risk of osteoporosis.
Why does it work? The poses (postures) used in this study put appropriate and equal stress on a variety of bones throughout the body--the hips, the wrists, the spine, and the arms. For example, in some poses the participants had to stand on one leg, forcing that leg to bear all the weight of the body--using more leg-muscle contraction to obtain better balance. That muscle force stresses the bone and kicks in the whole bone remodeling process that is so well explained above by Lanou & Castleman.
Downward Facing Dog Pose and Half Moon Pose stress the bones of the upper body, such as the chest, the back, arms, and wrists. Tree Pose and Warrior III stress the leg and hip bones. Triangle Pose stresses the back, hip, and legs. Doing all 5 poses continuously, and repetitively 3 times a week was enough to wake up the the body's bone remodeling system--resulting in a significant reduction of bone resorption/loss.
Anyone who regularly practices yoga would probably agree that there are far more than 5 poses that put stress on one's bones, muscles, and balance--and often far more than a free weight work-out. Plank pose, Chaturitanga, Up Dog, Eagle Pose, and toe balances--to name a few.
The Yoga Poses Used in the Study
Take Away Point: This was just a preliminary study, but certainly the results seem promising to me. Combined with the N=3 experience of my 2 friends & my yoga teacher--maybe yoga has real promise as a way to stave off osteoporosis, de-stress, and improve balance all at the same time. A 3-for-one exercise.
Don't Miss This Story of "How a Bone Disease Grew to Fit the Prescription", by NPR's Alix Spiegel. Click here to read or listen to the story. You can even read the full transcript if you don't want to miss any of it.
This first class piece of journalism will open your eyes to the whole controversy of whether or not osteopenia is a disease that needs to be treated with a drug. I'm choosing treatment with yoga, walking, weight-training, vitamin D, and lots of vegetables, especially the greens, and fruit. More on this later!
Do any yogis out there have some positive bone density scans to add validity to the Thailand study? I'd love to hear about it.