There is much disagreement about whether twisting poses are beneficial for people with osteoporosis or osteopenia. However, the torqueing action created by twisting can strengthen muscles, which can help bones stay in alignment, and can even build bone, since bone cells respond to stress by secreting bone-making proteins. The key, again, is to move mindfully, gently, smoothly, and with axial extension – lengthening the spine as you twist. All twisting movements should originate from the contraction of the abdomen on exhale. And I recommend repeating each movement several times: start with a very small movement and go deeper into the twist with each iteration. For osteoporosis, you may want to limit the degree of rotation.
Start each twist in a neutral position and as you inhale, imagine the spine getting longer – lengthening through the top of the head. This will create axial extension. Then keep that length as you exhale, contracting the abdominal muscles, and twist from that abdominal contraction. Be mindful NOT to power into a twist using the shoulders, arms, hips, or legs. Instead, twist from your core.
For fragile bones, it’s also important to avoid sudden movements. You can ensure that your movements are smooth by coordinating movement with breath. For example, start the exhale with a contraction of the abdomen, then continue to contract as you move into the twist. End the twist and the exhale together.