“In yoga, deep breathing is part of the practice of Pranayama. In Sanskrit, the ancient language of India, prana is the vital energy or life force; it also refers to respiration. Ayama means length, expansion, and extension, and conveys the idea of restraint, control, and stopping. According to B.K.S. Iyengar, Pranayama also means communication, expansion, or dimension. When practicing Pranayama, one slows down the rate of breathing and expands chest and lung capacity. Pranayama is an integral step in the eight-limbed path of yoga, Astanga Yoga, which strives to bring consciousness to mind and body, and finally, freedom.” – Dalia Zwick from The Diaphragm in Iyengar Yoga Pranayama and Physical Therapy
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