Pranayama

Prāṇāyāma is mentioned in verse 4.29 of the Bhagavad Gītā.[6]

According to Bhagavad-Gītā As It Is, prāṇāyāma is translated to "trance induced by stopping all breathing", also being made from the two separate Sanskrit words, prāṇa and āyām.[7]

Pranayama is the fourth "limb" of the eight limbs of Ashtanga Yoga mentioned in verse 2.29 in the Yoga Sutras of Patanjali.[8][9] Patanjali, a Hindu Rishi, discusses his specific approach to pranayama in verses 2.49 through 2.51, and devotes verses 2.52 and 2.53 to explaining the benefits of the practice.[10] Patanjali does not fully elucidate the nature of prana, and the theory and practice of pranayama seem to have undergone significant development after him.[11] He presents pranayama as essentially an exercise that is preliminary to concentration, as do the earlier Buddhist texts.[11]

Yoga teachers including B. K. S. Iyengar have advised that pranayama should be part of an overall practice that includes the other limbs of Patanjali's Raja Yoga teachings, especially Yama, Niyama, and Asana.[12]

The Indian tradition of Hatha Yoga makes use of various pranayama techniques. The 15th century Hatha Yoga Pradipika is a key text of this tradition and includes various forms of pranayama such as Kumbhaka breath retention and various body locks (Bandha).[13] Other forms of pranayama breathing include Ujjayi breath ("Victorious Breath"), Bhastrika ("Bellows Breath"), Kapalabhati ("Skull-shining Breath", a Shatkarma purification),[14] Surya Bhedana ("Sun-piercing Breath"),[15] and the soothing Bhramari (buzzing like a bee).[16] B. K. S. Iyengar cautions that pranayama should only be undertaken when one has a firmly established yoga practice and then only under the guidance of an experienced Guru.[12]

According to the scholar-practitioner of yoga Theos Bernard, the ultimate aim of pranayama is the suspension of breathing (kevala kumbhaka), "causing the mind to swoon".[17] Swami Yogananda writes, "The real meaning of Pranayama, according to Patanjali, the founder of Yoga philosophy, is the gradual cessation of breathing, the discontinuance of inhalation and exhalation".[18]

The yoga scholar Andrea Jain states that pranayama was "marginal to the most widely cited sources" before the 20th century, and that the breathing practices were "dramatically" unlike the modern ones; she writes that while pranayama in modern yoga as exercise consists of synchronising the breath with movements (between asanas), in texts like the Bhagavad Gita and the Yoga Sutras of Patanjali, pranayama meant "complete cessation of breathing", for which she cites Bronkhorst 2007.[19][20]

Later Indo-Tibetan developments in Buddhist pranayama which are similar to Hindu forms can be seen as early as the 11th century, in the Buddhist text titled the Amṛtasiddhi, which teaches three bandhas in connection with yogic breathing (kumbakha).[24]

Tibetan Buddhist breathing exercises such as the "nine breathings of purification" or the "Ninefold Expulsion of Stale Vital Energy" (rlung ro dgu shrugs), a form of alternate nostril breathing, commonly include visualizations.[25][26] In the Nyingma tradition of Dzogchen these practices are collected in the textual cycle known as "The Oral Transmission of Vairotsana" (Vai ro snyan brgyud).[27]

A Cochrane systematic review on the symptomatic relief of mild to moderate asthma by breathing exercises stated that there was limited evidence they might bring about improvement in quality of life, hyperventilation symptoms, and lung function.[28][29]

Although relatively safe, Hatha Yoga is not risk free. Beginners should avoid advanced moves and exercise within their capabilities. Functional limitations should be taken into consideration.[30] According to at least one study, pranayama was the yoga practice leading to most injuries, with four injuries in a study of 76 practitioners. There have been limited reports of adverse effects including haematoma and pneumothorax, though the connections are not always well established.[30]