The earliest references to hatha yoga are in Buddhist works dating from the eighth century.[200] The earliest definition of hatha yoga is found in the 11th century Buddhist text Vimalaprabha, which defines it in relation to the center channel, bindu etc.[201] Hatha yoga synthesizes elements of Patanjali's Yoga Sutras with posture and breathing exercises.[202] It marks the development of asanas (plural) into the full body 'postures' now in popular usage[186] and, along with its many modern variations, is the style that many people associate with the word yoga today.[203]
According to Georg Feuerstein, Laya yoga (yoga of dissolution or merging) "makes meditative absorption (laya) its focus. The laya-yogin seeks to transcend all memory traces and sensory experiences by dissolving the microcosm, the mind, in the transcendental Self-Consciousness."[277] There are various forms and techniques of Laya yoga, including listening to the "inner sound" (nada), practicing various mudras like Khechari mudra and Shambhavi mudra as well as techniques meant to awaken a spiritual energy in the body (kundalini).[278]
There is no consensus on its chronology or specific origin other than that yoga developed in ancient India. Suggested origins are the Indus Valley Civilization (3300–1900 BCE)[44] and pre-Vedic Eastern states of India,[45] the Vedic period (1500–500 BCE), and the śramaṇa movement.[46] According to Gavin Flood, continuities may exist between those various traditions:
The earliest extant systematic account of yoga and a bridge from the earlier Vedic uses of the term is found in the Hindu Katha Upanisad (Ku), a scripture dating from about the third century BCE[…] [I]t describes the hierarchy of mind-body constituents—the senses, mind, intellect, etc.—that comprise the foundational categories of Sāmkhya philosophy, whose metaphysical system grounds the yoga of the Yogasutras, Bhagavad Gita, and other texts and schools (Ku3.10–11; 6.7–8).[101]
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).[9][100][104]
Muscle growth is more difficult to achieve in older adults than younger adults because of biological aging, which leads to many metabolic changes detrimental to muscle growth; for instance, by diminishing growth hormone and testosterone levels. Some recent clinical studies have shown that low-dose HGH treatment for adults with HGH deficiency changes the body composition by increasing muscle mass, decreasing fat mass, increasing bone density and muscle strength, improves cardiovascular parameters, and affects the quality of life without significant side effects.[46][47][unreliable medical source?][48]
In the early 2000s, the IFBB was attempting to make bodybuilding an Olympic sport. It obtained full IOC membership in 2000 and was attempting to get approved as a demonstration event at the Olympics, which would hopefully lead to it being added as a full contest. This did not happen and Olympic recognition for bodybuilding remains controversial since many argue that bodybuilding is not a sport.[11]
The early practice of Jain yoga seems to have been divided into several types, including meditation (dhyāna), abandonment of the body (kāyotsarga), contemplation (anuprekṣā), and reflection (bhāvanā).[256] Some of the earliest sources for Jain yoga are the Uttarādhyayana-sūtra, the Āvaśyaka-sūtra, the Sthananga Sutra (c. 2nd century BCE). Later works include Kundakunda's Vārassa-aṇuvekkhā (“Twelve Contemplations”, c. 1st century BCE to 1st century CE), Haribhadra's Yogadṛṣṭisamuccya (8th century) and the Yogaśāstra of Hemachandra (12th century). Later forms of Jain yoga adopted Hindu influences, such as ideas from Patanjali's yoga and later Tantric yoga (in the works of Haribhadra and Hemachandra respectively). The Jains also developed a progressive path to liberation through yogic praxis, outlining several levels of virtue called gunasthanas.

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.[8][note 2] The chronology of earliest texts describing yoga-practices is unclear, varyingly credited to Upanishads.[9] The Yoga Sutras of Patanjali date from the first half of the 1st millennium CE,[10][11] but only gained prominence in the West in the 20th century.[12] Hatha yoga texts emerged sometimes between the 9th and 11th century with origins in tantra.[13][14]