| If you find it uncomfortable holding the breath while the posture is held, breath gently through the nostrils. Some may find that they are able to arch the spine back even more than in the initial arch in step 3. In this case try "walking" the hands toward the pelvic region and stretching the head further back.
In addition to the obvious benefits to the spine and lower back, the standard variation of the naga-asana strengthens the wrists and stretches the muscles in the chest. By maintaining a constant exertion to create a greater arch in the spine, the stomach and pelvic muscles are strengthened. Greater strength in these areas can be cultivated by performing the variation where the arms remain on the ground. B.K.S. Iyengar, a renowned expert in yoga-asanas, claims that displaced spinal discs can be placed back in their original position by practicing the naga-asana.
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The Yoga Sutras
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