Yoga

Yoga (ヨガ) is a class of spiritual practices, meditation and physical exercises, originating from ancient India.

Besides the modern variety seen more as a, there are various schools and applications of yoga in a mystical context, including ones in Hinduism and Buddhism, and as such, it can be utilized in the field of magic.

Principles
Rather than just a done at a gym, as it is often seen in recent times, yoga is a method of controlling one's inner body through breathing to have an effect on the outside world. Tools are not usually needed, and practitioners are meant to rid themselves of all worldly thoughts and possessions during the action.

In yoga meditations, mental stability is gained by passing power through various points in the body.

One of the modern varieties of is, which is performed in hot and humid conditions.

Background
After being ostracized from the Golden Dawn, Allan Bennett travelled to the East and learned yoga in, recovering from his opium addiction, and becoming a Buddhist monk under the name Swami Maitrananda, apparently gaining a body so healthy that one could swear he was a different person altogether.

Yoga was one of several methods which Aleister Crowley used to measure his limits. At some point, Dion Fortune tried to explain Kabbalah using yoga as an example.

Aleister Crowley Arc
During the events in the Windowless Building on December 11th, yoga was mentioned as one of the various methods which Aleister Crowley had used in the past to measure his limits.

Coronzon Arc
While instructing Hamazura Shiage in refining magical power to revive the recreated Dion Fortune, Coronzon brought out a yoga mat from the supply of tools in the Queen Britannia's temple, one which was apparently used by a princess in the past.

Christmas Day Arc
Yoga was mentioned during Touma and St. Germain's battle with Anna Sprengel on Christmas Day, having been referenced on a sign in a jewel store touched by R&C Occultics, which had an offer to create a personal incense to add something extra to yoga sessions. St. Germain remarked on how one was supposed to rid themselves of worldly thoughts and possessions while doing it, though beginners might find it easier to focus on their breathing if the air was given an aroma or color - adding that using a guide meant only following rails laid out from them, so the act would lose meaning.

Toaru Majutsu no Virtual-On: Misaka Mikoto's Dangerous Tea Party
When Misaka Mikoto took Shokuhou Misaki to the Rude Cafe for a discussion about the Vooster's Cup, Shokuhou expressed a wish to do some on the way there. After their time in the cafe, the two had a hot yoga session in the building's gym while their clothes were being cleaned.