According to Crangle, some researchers have favoured a linear theory, which attempts "to interpret the origin and early development of Indian contemplative practices as a sequential growth from an Aryan genesis",[note 4] just like traditional Hinduism regards the Vedas to be the ultimate source of all spiritual knowledge.[note 5] Thomas McEvilley favors a composite model where pre-Aryan yoga prototype existed in the pre-Vedic period and its refinement began in the Vedic period.
Samuel states that Tantrism is a contested concept. Tantra yoga may be described, according to Samuel, as practices in 9th to 10th century Buddhist and Hindu (Saiva, Shakti) texts, which included yogic practices with elaborate deity visualizations using geometrical arrays and drawings (mandala), fierce male and particularly female deities, transgressive life stage related rituals, extensive use of chakras and mantras, and sexual techniques, all aimed to help one's health, long life and liberation.
Theosophists including Madame Blavatsky also had a large influence on the Western public's view of Yoga. Esoteric views current at the end of the 19th century provided a further basis for the reception of Vedanta and of Yoga with its theory and practice of correspondence between the spiritual and the physical. The reception of Yoga and of Vedanta thus entwined with each other and with the (mostly Neoplatonism-based) currents of religious and philosophical reform and transformation throughout the 19th and early 20th centuries. Mircea Eliade brought a new element into the reception of Yoga with the strong emphasis on Tantric Yoga in his seminal book: Yoga: Immortality and Freedom. With the introduction of the Tantra traditions and philosophy of Yoga, the conception of the "transcendent" to be attained by Yogic practice shifted from experiencing the "transcendent" ("Atman-Brahman" in Advaitic theory) in the mind to the body itself.
Similarly, Brahma sutras – the foundational text of the Vedanta school of Hinduism, discusses yoga in its sutra 2.1.3, 2.1.223 and others. Brahma sutras are estimated to have been complete in the surviving form sometime between 450 BCE to 200 CE, and its sutras assert that yoga is a means to gain "subtlety of body" and other powers. The Nyaya sutras – the foundational text of the Nyaya school, variously estimated to have been composed between the 6th-century BCE and 2nd-century CE, discusses yoga in sutras 4.2.38–50. This ancient text of the Nyaya school includes a discussion of yogic ethics, dhyana (meditation), samadhi, and among other things remarks that debate and philosophy is a form of yoga.
In 1989 and 2003, the Vatican issued two documents: Aspects of Christian meditation and "A Christian reflection on the New Age," that were mostly critical of eastern and New Age practices. The 2003 document was published as a 90-page handbook detailing the Vatican's position. The Vatican warned that concentration on the physical aspects of meditation "can degenerate into a cult of the body" and that equating bodily states with mysticism "could also lead to psychic disturbance and, at times, to moral deviations." Such has been compared to the early days of Christianity, when the church opposed the gnostics' belief that salvation came not through faith but through a mystical inner knowledge. The letter also says, "one can see if and how [prayer] might be enriched by meditation methods developed in other religions and cultures" but maintains the idea that "there must be some fit between the nature of [other approaches to] prayer and Christian beliefs about ultimate reality." Some[which?] fundamentalist Christian organizations consider yoga to be incompatible with their religious background, considering it a part of the New Age movement inconsistent with Christianity.
The Maitrayaniya Upanishad, likely composed in a later century than Katha and Shvetashvatara Upanishads but before Patanjali's Yoga Sutra, mentions sixfold yoga method – breath control (pranayama), introspective withdrawal of senses (pratyahara), meditation (dhyana), mind concentration (dharana), philosophical inquiry/creative reasoning (tarka), and absorption/intense spiritual union (samadhi).
^ James Mallinson, "Sāktism and Hathayoga," 28 June 2012.
Archived 16 June 2013 at the Wayback Machine [accessed 19 September 2013] pgs. 2 "The earliest references to hathayoga are scattered mentions in Buddhist canonical works and their exegesis dating from the eighth century onwards, in which it is the soteriological method of last resort."
^ Gavin Flood: "These renouncer traditions offered a new vision of the human condition which became incorporated, to some degree, into the worldview of the Brahman householder. The ideology of asceticism and renunciation seems, at first, discontinuous with the brahmanical ideology of the affirmation of social obligations and the performance of public and domestic rituals. Indeed, there has been some debate as to whether asceticism and its ideas of retributive action, reincarnation and spiritual liberation, might not have originated outside the orthodox vedic sphere, or even outside Aryan culture: that a divergent historical origin might account for the apparent contradiction within 'Hinduism' between the world affirmation of the householder and the world negation of the renouncer. However, this dichotomization is too simplistic, for continuities can undoubtedly be found between renunciation and vedic Brahmanism, while elements from non-Brahmanical, Sramana traditions also played an important part in the formation of the renunciate ideal. Indeed there are continuities between vedic Brahmanism and Buddhism, and it has been argued that the Buddha sought to return to the ideals of a vedic society which he saw as being eroded in his own day."
^ James Mallinson, "Sāktism and Hathayoga," 6 March 2012. PDF file Archived 16 June 2013 at the Wayback Machine [accessed 10 June 2012] pp. 20–21 "The Buddha himself is said to have tried both pressing his tongue to the back of his mouth, in a manner similar to that of the hathayogic khecarīmudrā, and ukkutikappadhāna, a squatting posture which may be related to hathayogic techniques such as mahāmudrā, mahābandha, mahāvedha, mūlabandha, and vajrāsana in which pressure is put on the perineum with the heel, in order to force upwards the breath or Kundalinī."
An influential text which teaches yoga from an Advaita perspective of nondualistic idealism is the Yoga-Vāsiṣṭha. This work uses numerous short stories and anecdotes to illustrate its main ideas. It teaches seven stages or bhumis of yogic practice. It was a major reference for medieval Advaita Vedanta yoga scholars and before the 12th century, it was one of the most popular texts on Hindu yoga.
The motor proteins actin and myosin generate the forces exerted by contracting muscles. Current recommendations suggest that bodybuilders should consume 25–30% of protein per total calorie intake to further their goal of maintaining and improving their body composition. This is a widely debated topic, with many arguing that 1 gram of protein per pound of body weight per day is ideal, some suggesting that less is sufficient, while others recommending 1.5, 2, or more. It is believed that protein needs to be consumed frequently throughout the day, especially during/after a workout, and before sleep. There is also some debate concerning the best type of protein to take. Chicken, turkey, beef, pork, fish, eggs and dairy foods are high in protein, as are some nuts, seeds, beans, and lentils. Casein or whey are often used to supplement the diet with additional protein. Whey protein is the type of protein contained in many popular brands of protein supplements and is preferred by many bodybuilders because of its high Biological Value (BV) and quick absorption rates. Whey protein also has a bigger effect than casein on insulin levels, triggering about double the amount of insulin release. That effect is somewhat overcome by combining casein and whey. Bodybuilders are usually thought to require protein with a higher BV than that of soy, which is additionally avoided due to its claimed estrogenic properties. Still, some nutrition experts believe that soy, flax seeds and many other plants that contain the weak estrogen-like compounds or phytoestrogens, can be used beneficially, as phytoestrogens compete with estrogens for receptor sites in the male body and can block its actions. This can also include some inhibition of pituitary functions while stimulating the P450 system (the system that eliminates hormones, drugs and metabolic waste product from the body) in the liver to more actively process and excrete excess estrogen. Cortisol decreases amino acid uptake by muscle, and inhibits protein synthesis.
According to Pāṇini, the term yoga can be derived from either of two roots, yujir yoga (to yoke) or yuj samādhau ("to concentrate"). In the context of the Yoga Sutras of Patanjali, the root yuj samādhau (to concentrate) is considered by traditional commentators as the correct etymology. In accordance with Pāṇini, Vyasa who wrote the first commentary on the Yoga Sutras, states that yoga means samādhi (concentration).