^ James Mallinson, "Sāktism and Hathayoga," 6 March 2012. PDF file Archived 16 June 2013 at the Wayback Machine [accessed 10 June 2012] pp. 20–21 "The Buddha himself is said to have tried both pressing his tongue to the back of his mouth, in a manner similar to that of the hathayogic khecarīmudrā, and ukkutikappadhāna, a squatting posture which may be related to hathayogic techniques such as mahāmudrā, mahābandha, mahāvedha, mūlabandha, and vajrāsana in which pressure is put on the perineum with the heel, in order to force upwards the breath or Kundalinī."
Yoga may have pre-Vedic elements. Some state yoga originated in the Indus Valley Civilization. Marshall, Eliade and other scholars note that the Pashupati seal discovered in an Indus Valley Civilization site depicts a figure in a position resembling an asana used for meditation, Mulabandhasana. This interpretation is considered speculative and uncertain by more recent analysis of Srinivasan and may be a case of projecting "later practices into archeological findings".
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.