The origins of yoga have been speculated to date back to pre-Vedic Indian traditions; it is mentioned in the Rigveda,[note 1] but most likely developed around the sixth and fifth centuries BCE, in ancient India's ascetic and śramaṇa movements.[note 2] The chronology of earliest texts describing yoga-practices is unclear, varyingly credited to Upanishads. The Yoga Sutras of Patanjali date from the first half of the 1st millennium CE, but only gained prominence in the West in the 20th century. Hatha yoga texts emerged sometimes between the 9th and 11th century with origins in tantra.
The chronology of completion of these yoga-related Early Buddhist Texts, however, is unclear, just like ancient Hindu texts. Early known Buddhist sources like the Majjhima Nikāya mention meditation, while the Anguttara Nikāya describes Jhāyins (meditators) that resemble early Hindu descriptions of Muni, Kesins and meditating ascetics, but these meditation-practices are not called yoga in these texts. The earliest known specific discussion of yoga in the Buddhist literature, as understood in modern context are from the later Buddhist Yogācāra and Theravada schools.
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.
^ On the dates of the Pali canon, Gregory Schopen writes, "We know, and have known for some time, that the Pali canon as we have it — and it is generally conceded to be our oldest source — cannot be taken back further than the last quarter of the first century BCE, the date of the Alu-vihara redaction, the earliest redaction we can have some knowledge of, and that — for a critical history — it can serve, at the very most, only as a source for the Buddhism of this period. But we also know that even this is problematic... In fact, it is not until the time of the commentaries of Buddhaghosa, Dhammapala, and others — that is to say, the fifth to sixth centuries CE — that we can know anything definite about the actual contents of [the Pali] canon."
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.