Did you know that the bones of our skeleton are a living tissue? There are over two hundred individual bones in our body. Bones support our weight and in combination with muscles, ligaments, and tendons allow for complex movements. They also function as a repository of minerals that are used by the body. Like most of our living tissues, bones are in a constant state of flux through a process called resorption and formation. Resorption is when calcium is removed from the bones for critical functions needed in the body; formation is the replacement of old bone with new. By the age of thirty, both men and women have reached their peak bone mass. As we continue to age this remodeling can become unbalanced due to diet, medications, medical conditions and lifestyle choices causing an increase in the breakdown of bones compared to rebuilding which can ultimately lead to osteoporosis. 
Bones are made up of two essential types of tissue called compact bone (densely packed bone such as found in our arm and leg bones) and trabecular bone (less dense and spongier than compact bone such as found in our vertebrae) and most of our bones are a combination of these two types of bone tissue. 
Bone tissue is composed of Type I collagen which forms the interior scaffolding of the bone, Calcium (which is the main ingredient of bone) and Phosphorus crystals that add strength to the bone, and the bone cells that are responsible for the bone break down and remodeling throughout our life. In order to maintain strong and healthy bones, many studies have shown that we need a balanced lifestyle consisting of a nutritious diet, sunlight, and exercise where force is applied to bone throughout our early childhood, adolescence, and adulthood.
A nutritious diet for bone health requires twelve essential nutrients: Calcium, Vit. D, Fluoride, Magnesium, Potassium, Protein, Vit A, C, B6, Folate, Vit B12, K. Additionally, exposure to sunlight is important as it converts raw Vitamin D into active Vitamin D which helps limit withdrawals of calcium from the bones.
According to plentiful scientific studies, the two proven exercise approaches to building bone are strength training and weight-bearing. Many experts in the field also tell us that impact exercises are best for staving off bone loss but yet another group of experts caution impact exercises stating it can lead to osteoporosis. 
So, is Yoga good for our bones? While there is no current scientific research that has conclusively demonstrated that yoga builds bones, there are several recent studies suggesting that bone quality is improved as a result of the practice of Yoga. If our bones respond to weight-bearing and strength training we can tailor our Yoga practice to include weight-bearing poses. For the wrists and arms, these poses may include Cobra, Downward Dog, and Crow which stimulate bone building in the upper body. Balance poses such as Tree, Eagle Pose and Warrior III–where the weight of the body is transferred onto the supporting leg–stimulate bone building in the lower extremity. Strength training occurs in Yoga when we use the weight of our own body such as performing Chatarunga or Plank Pose. There is some controversy about twists or rotation poses and flexion of the spine poses in Yoga specifically for people with osteopenia or osteoporosis. Dr. Fishman who wrote “Yoga for Osteoporosis” claims that gentle twisting poses can strengthen the anterior portion of the vertebral bodies. Others claim that twists increase stress on the anterior vertebral bodies and over time could lead to a vertebral fracture. Flexion of the spine or slouching poses also impose a lot of stress on the spine which could lead to a vertebral fracture over time. Fortunately, with Yoga there are many ways for you or a knowledgeable Yoga instructor to creatively and safely adapt the poses to suit your individual needs. 
If indeed our bones respond favorably to force, then Yoga is a wonderful, impact-free way of applying force. It can safely stress the bones without impact which is important for people who have arthritic or painful joints. A consistent yoga practice has been found to improve balance, range of motion and strength, and bone health throughout our life. But, as with all things involving physicality and movement, please be aware and knowledgeable about your body and personal precautions and/or contraindications. I have listed some assessment tools and information if you are curious about the health of your bones at any stage of your life.
Stay strong!
Patsy Tyler, DPT, RYT
Patsy is a physical therapist at our practice and leads weekly drop-in classes and series at our studio. Join her for one of these upcoming series: Yoga for a Healthy Back beginning Tuesday, Mar 3 or Strong Bones, Balanced Body, starting Mar 23. Sign up here
www.sciatica.org  (click on Osteoporosis)
Fishman L, Saltonstall E. Yoga for Osteoporosis. WW Norton and Company. 2010
Martin M. Yoga for Better Bones. Kamajojo Press. 2016
Martin M. Exercise for Better Bones. Kamajojo Press. 2016
Watson S, Pendick D. Osteoporosis. A Guide to Prevention and Treatment. Harvard Medical School. 2016
Bone Health. Linus Pauling Institute

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