Alexander Wynne observes that formless meditation and elemental meditation might have originated in the Upanishadic tradition.[93] The earliest reference to meditation is in the Brihadaranyaka Upanishad, one of the oldest Upanishads.[67] Chandogya Upanishad describes the five kinds of vital energies (prana). Concepts used later in many yoga traditions such as internal sound and veins (nadis) are also described in the Upanishad.[59] Taittiriya Upanishad defines yoga as the mastery of body and senses.[94]

Niyama (The five "observances"): Śauca (purity, clearness of mind, speech and body),[152] Santosha (contentment, acceptance of others and of one's circumstances),[153] Tapas (persistent meditation, perseverance, austerity),[154] Svādhyāya (study of self, self-reflection, study of Vedas),[155] and Ishvara-Pranidhana (contemplation of God/Supreme Being/True Self).[153]
Yoga (/ˈjoʊɡə/;[1] Sanskrit: योग; pronunciation) is a group of physical, mental, and spiritual practices or disciplines which originated in ancient India. Yoga is one of the six orthodox schools of Hindu philosophical traditions.[2] There is a broad variety of yoga schools, practices, and goals[3] in Hinduism, Buddhism, and Jainism.[4][5][6] The term "yoga" in the Western world often denotes a modern form of Hatha yoga, yoga as exercise, consisting largely of the postures called asanas.
Ascetic practices (tapas), concentration and bodily postures used by Vedic priests to conduct yajna (sacrifice), might have been precursors to yoga.[note 9] Vratya, a group of ascetics mentioned in the Atharvaveda, emphasized on bodily postures which may have evolved into yogic asanas.[59] Early Samhitas also contain references to other group ascetics such as munis, the keśin, and vratyas.[67] Techniques for controlling breath and vital energies are mentioned in the Brahmanas (texts of the Vedic corpus, c. 1000–800 BCE) and the Atharvaveda.[59][72] Nasadiya Sukta of the Rig Veda suggests the presence of an early contemplative tradition.[note 10]
Description of an early form of yoga called nirodhayoga (yoga of cessation) is contained in the Mokshadharma section of the 12th chapter (Shanti Parva) of the Mahabharata (third century BCE).[109] Nirodhayoga emphasizes progressive withdrawal from the contents of empirical consciousness such as thoughts, sensations etc. until purusha (Self) is realized. Terms like vichara (subtle reflection), viveka (discrimination) and others which are similar to Patanjali's terminology are mentioned, but not described.[110] There is no uniform goal of yoga mentioned in the Mahabharata. Separation of self from matter, perceiving Brahman everywhere, entering into Brahman etc. are all described as goals of yoga. Samkhya and yoga are conflated together and some verses describe them as being identical.[111] Mokshadharma also describes an early practice of elemental meditation.[112] Mahabharata defines the purpose of yoga as the experience of uniting the individual ātman with the universal Brahman that pervades all things.[111]
Equipment required? No. You don't need any equipment because you'll rely on your own body weight for resistance. But you'll probably want to use a yoga mat to keep you from sliding around in standing poses, and to cushion you while in seated and lying positions. Other, optional equipment includes a yoga ball for balance, a yoga block or two, and straps to help you reach for your feet or link your hands behind your back.

^ James Mallinson, "Sāktism and Hathayoga," 28 June 2012. Archived 16 June 2013 at the Wayback Machine [accessed 19 September 2013] pgs. 2 "In its earliest definition, in Pundarīka's eleventh-century Vimalaprabhā commentary on the Kālacakratantra, hathayoga is said to bring about the "unchanging moment" (aksaraksana) "through the practice of nāda by forcefully making the breath enter the central channel and through restraining the bindu of the bodhicitta in the vajra of the lotus of wisdom". While the means employed are not specified, the ends, in particular restraining bindu, semen, and making the breath enter the central channel, are similar to those mentioned in the earliest descriptions of the practices of hathayoga, to which I now turn."

The meaning of health has evolved over time. In keeping with the biomedical perspective, early definitions of health focused on the theme of the body's ability to function; health was seen as a state of normal function that could be disrupted from time to time by disease. An example of such a definition of health is: "a state characterized by anatomic, physiologic, and psychological integrity; ability to perform personally valued family, work, and community roles; ability to deal with physical, biological, psychological, and social stress".[7] Then in 1948, in a radical departure from previous definitions, the World Health Organization (WHO) proposed a definition that aimed higher: linking health to well-being, in terms of "physical, mental, and social well-being, and not merely the absence of disease and infirmity".[8] Although this definition was welcomed by some as being innovative, it was also criticized as being vague, excessively broad and was not construed as measurable. For a long time, it was set aside as an impractical ideal and most discussions of health returned to the practicality of the biomedical model.[9]