One of the best known early expressions of Brahmanical Yoga thought is the Yoga Sutras of Patanjali , the original name of which may have been the Pātañjalayogaśāstra-sāṃkhya-pravacana (c. sometime between 325 - 425) which some scholars now believe included both the sutras and a commentary. As the name suggests, the metaphysical basis for this text is the Indian philosophy termed Sāṃkhya. This atheistic school is mentioned in Kauṭilya's Arthashastra as one of the three categories of anviksikis (philosophies) along with Yoga and Cārvāka. The two schools have some differences as well. Yoga accepted the conception of "personal god", while Samkhya developed as a rationalist, non-theistic/atheistic system of Hindu philosophy. Sometimes Patanjali's system is referred to as Seshvara Samkhya in contradistinction to Kapila's Nirivara Samkhya. The parallels between Yoga and Samkhya were so close that Max Müller says that "the two philosophies were in popular parlance distinguished from each other as Samkhya with and Samkhya without a Lord."
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). 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.
Many trainees like to cycle between the two methods in order to prevent the body from adapting (maintaining a progressive overload), possibly emphasizing whichever method more suits their goals; typically, a bodybuilder will aim at sarcoplasmic hypertrophy most of the time but may change to a myofibrillar hypertrophy kind of training temporarily in order to move past a plateau. However, no real evidence has been provided to show that trainees ever reach this plateau, and rather was more of a hype created from "muscular confusion".[clarification needed]
Core: Yes. There are yoga poses to target just about every core muscle. Want to tighten those love handles? Then prop yourself up on one arm and do a side plank. To really burn out the middle of your abs, you can do boat pose, in which you balance on your "sit bones" (the bony prominences at the base of your pelvic bones) and hold your legs up in the air.