The system of Ashtanga yoga is an ancient one that has been passed down through the centuries. It was taught by the Vamana Rishi in the Yoga Korunta. The Yoga Korunta is an ancient text whose origins are unknown. It is believed to have been compiled by the sage Vamana Rishi. It is believed to contain various asana groupings and original teachings in other areas. The text was handed down, many accounts indicate orally, in the early 1900s to Sri Tirumalai Krishnamacharya by his teacher, Rama Mohan Brahmachari. When Sri K. Pattabhi Jois studied with Krishnamacharya at Mysore in 1927, the text was reportedly passed down to him.

Ashtanga yoga, also known as "power yoga," is said to be an aerobic form of yoga. It is very strenuous and physically demanding. The practice of Ashtanga involves six series of linked postures and are progressively difficult. Each series requires anywhere from 90 minutes to three hours to complete.

Ashtanga is structured so that you must go through the entire series of postures several times in succession. Some of the postures are difficult to even displeasing. The series themselves work like an intricate puzzle lock. By doing specific postures in the correct order, the lock snaps and the mind and body are opened automatically.

Each of the six series targets, or unlocks, a specific part of the mind and body. The main series, yoga chikitsa or yoga therapy, is intended to realign and detoxify the physical body with an emphasis on the spine. It lays the foundation for building great physical strength. After the primary series is the intermediate series, referred to as nadi shodana. Nadi shodana means cleansing of the nadis or channels or river. As the name indicates, this series purifies the nervous system and strengthens it as well as the energy channels that form the network linking the seven chakras.

Following the yoga chikitsa and the nadi shodana are four advanced series. These four series were once taught as two, but they were eventually divided into four series total so that they could be more accessible. Collectively, these four series are known as sthira bhaga, or divine stability. These series involve heightened and advanced flexibility, strength, energy flow and concentration that are initiated and cultivated in the first two series.

When taking an Ashtanga class, it will typically open with a Sanskrit prayer. When the changing subsides, the teacher will remind students to deploy the three central techniques of Ashtanga: ujjayi breathing, mula bandha and uddiyana bandha.

* Ujjayi Breathing - also known as the "victorious breath," ujjayi breathing is a classic pranayama technique. In this technique, the breath passes across the back of the throat which creates a hissing sound. This method is used throughout the series of Ashtanga yoga. It is beneficial because it keeps the breath controlled and stead, drawing the attention of the mind inward. This greatly facilitates meditation in motion.

* Mula Bandha - known at the "root lock," is an energy raising custom that is traditionally used in hatha yoga. Many schools, however, do not use mula bandha during asana practice. Mula bandha is essential to the process and practice of Ashtanga yoga because it intensifies the energy at the base of the spine, drawing it upward while drawing awareness to the core of the body.

* Uddiyana Bandha - or upward lock, is a powerful side effect of a strong mula bandha, occurring automatically. During uddiyana bandha, the lower belly, just below the navel, draws inward as the abdomen firms. The breath is drawn upward, expanding the lungs, chest and ribcage. During this process, however, the diaphragm does not become hard, it remains soft and is able to move freely. When practiced regularly, over a period of time, uddiyana bandha can help to increase lung capacity.

Each of the three techniques should be practiced continuously and together throughout the Ashtanga series. This increases the challenge in the exercise in concentration. Once the breathing is established and the locks are engaged, the Sun Salutations series are begun to warm up the body. Tapas, or heat, is one of the core principles of Ashtanga yoga. The general gist is that the more you sweat, the better and more beneficial the session. The postures are demanding, encouraging profuse perspiration.

After the standing poses, the body is warmed up sufficiently, allowing the progression to the sequences that are unique to each individual series. While each series is in and of itself a balanced workout, each has its own focus.

Each series culminates in finishing poses that create a cool down sequence, including seated meditation. It also involves a prolonged respite in the corpse pose or savasana. The finishing poses return the body's metabolic rate to normal and give it balance. It allows the nervous system to absorb the benefits.