Many people choose to forgo food from animal sources to varying degrees (e.g. flexitarianism, pescetarianism, vegetarianism, veganism) for health reasons, issues surrounding morality, or to reduce their personal impact on the environment, although some of the public assumptions about which diets have lower impacts are known to be incorrect. Raw foodism is another contemporary trend. These diets may require multivitamin supplements to meet ordinary nutritional needs.
Tantra is a range of esoteric traditions that began to arise in India no later than the 5th century CE.[note 17] George Samuel states, "Tantra" is a contested term, but may be considered as a school whose practices appeared in mostly complete form in Buddhist and Hindu texts by about 10th century CE. Tantric yoga developed complex visualizations which included meditation on the body as a microcosm of the cosmos. They included also the use of mantras, pranayama, and the manipulation of the subtle body, including its nadis and cakras. These teachings on cakras and Kundalini would become central to later forms of Indian Yoga.
^ Andrew J. Nicholson (2013). Unifying Hinduism: Philosophy and Identity in Indian Intellectual History. Columbia University Press. p. 26. ISBN 978-0-231-14987-7., Quote: "From a historical perspective, the Brahmasutras are best understood as a group of sutras composed by multiple authors over the course of hundreds of years, most likely composed in its current form between 400 and 450 BCE."
Alexander the Great reached India in the 4th century BCE. Along with his army, he took Greek academics with him who later wrote memoirs about geography, people and customs they saw. One of Alexander's companion was Onesicritus, quoted in Book 15, Sections 63–65 by Strabo, who describes yogins of India. Onesicritus claims those Indian yogins (Mandanis ) practiced aloofness and "different postures – standing or sitting or lying naked – and motionless".
The Yoga Sutras are also influenced by the Sramana traditions of Buddhism and Jainism, and may represent a further Brahmanical attempt to adopt yoga from the Sramana traditions. As noted by Larson, there are numerous parallels in the concepts in ancient Samkhya, Yoga and Abhidharma Buddhist schools of thought, particularly from 2nd century BCE to 1st century AD. Patanjali's Yoga Sutras is a synthesis of these three traditions. From Samkhya, the Yoga Sutras adopt the "reflective discernment" (adhyavasaya) of prakrti and purusa (dualism), its metaphysical rationalism, as well its three epistemic methods of gaining reliable knowledge. From Abhidharma Buddhism's idea of nirodhasamadhi, suggests Larson, Yoga Sutras adopt the pursuit of altered state of awareness, but unlike Buddhism's concept of no self nor soul, Yoga is physicalist and realist like Samkhya in believing that each individual has a self and soul. The third concept Yoga Sutras synthesize into its philosophy is the ancient ascetic traditions of meditation and introspection, as well as the yoga ideas from middle Upanishads such as Katha, Shvetashvatara and Maitri.
The spiritual sense of the word yoga first arises in Epic Sanskrit, in the second half of the 1st millennium BCE, and is associated with the philosophical system presented in the Yoga Sutras of Patanjali, with the chief aim of "uniting" the human spirit with the Divine. The term kriyāyoga has a technical meaning in the Yoga Sutras (2.1), designating the "practical" aspects of the philosophy, i.e. the "union with the supreme" due to performance of duties in everyday life.
^ * Wynne states that "The Nasadiyasukta, one of the earliest and most important cosmogonic tracts in the early Brahminic literature, contains evidence suggesting it was closely related to a tradition of early Brahminic contemplation. A close reading of this text suggests that it was closely related to a tradition of early Brahminic contemplation. The poem may have been composed by contemplatives, but even if not, an argument can be made that it marks the beginning of the contemplative/meditative trend in Indian thought."
The first Hindu teacher to actively advocate and disseminate aspects of yoga, not including asanas, to a western audience, Swami Vivekananda, toured Europe and the United States in the 1890s. The reception which Swami Vivekananda received built on the active interest of intellectuals, in particular the New England Transcendentalists, among them Ralph Waldo Emerson (1803–1882), who drew on German Romanticism and philosophers and scholars like G. W. F. Hegel (1770–1831), the brothers August Wilhelm Schlegel (1767–1845) and Karl Wilhelm Friedrich Schlegel (1772–1829), Max Mueller (1823–1900), Arthur Schopenhauer (1788–1860), and others who had (to varying degrees) interests in things Indian.
An article by Muscle & Fitness magazine, "Overtrain for Big Gains", claimed that overtraining for a brief period can be beneficial. Overtraining can be used advantageously, as when a bodybuilder is purposely overtrained for a brief period of time to super compensate during a regeneration phase. These are known as "shock micro-cycles" and were a key training technique used by Soviet athletes.