Directly or indirectly, all Yogic techniques have an effect on purifying the nadis and awakening the Kundalini energy, with varying degrees of effectiveness. I wish to provide an overview of different suggested techniques from various aspects of the practice of Yoga.
Alternate Nostril Breathing
Swami Sivananda states that “pranayama brings about the quick purification of the nadis” (Sivananda, 2005, p. 81). Out of all the breathing techniques included in pranayama, alternate nostril breathing is of particular interest. This technique consists of breathing cyclically through both nostrils: one inhales through the left, and exhales through the right, and begins the process again inhaling through the right.
Asanas
Asanas, or Yogic postures, also have an effect in the nadis. For instance, Paschimottanasana, or seating forward bend stimulates all the abdominal organs including the kidneys, pancreas and liver. This posture keeps the “epigastric plexus, the bladder, the prostrate and the sympathetic cord healthy” and also “makes the breath flow through the Sushumma” (Sivananda, 2005, p. 109)
Bandhas
Bandhas, or energy locks, are also effective means of redirecting energy within the body and awakening the Kundalini. These techniques are usually practiced during retention of the breath between the inhalation and the exhalation, and consist of contracting the neck, abdominal and/or sphincter muscles. For instance, Uddiyana Bandha, or abdominal energy lock, received its named because through its practice the prana can travel through the Sushumma nadi (Sivananda, 2005, p. 121).
Kriyas
In Yoga, Kriyas are exercises to bring about purification of the nadis by cleaning the body. Techniques include cleaning the colon, the digestive track, and the eyes. Yoga suggests that the nostrils are cleaned every day using a technique called neti, which involves water, a rubber catheter, or cotton to remove mucus from the nostrils. Physiologically, we can see how this technique removes an extra source of irregularity in the nostril cycle, namely excessive mucus that prevents decongestion of the nostrils.
Gopi Krishna’s interpretation
An interesting interpretation by Yoga practitioner Gopi Krishna is that many Yogic techniques force the body to make drastic adjustments, which stimulate the Kundalini energy to preserve life (Krishna, 1993, p. 21). Among such techniques, he mentions that during breathing exercises, especially breath retention, greatly limit the supply of oxygen to the brain. This interpretation is valid and worth mentioning. However, I believe that all Yogic techniques require gradual process, and never put a risk to life. The process of awakening Kundalini is much more comprehensive, and can be achieved by others means that do not involve techniques that have a direct effect in oxygen levels or metabolic activity.
Holistic Medicine
In Ayurvedic Medicine, the Ida and the Pingala are stimulated by using aromatherapy, applying medicated oils or pressure to the nostrils (Frawley, 2002, p. 162). Note that the main focus of holistic medicine is to bring about physical balance and health, and their techniques do not involve previous knowledge of Yoga.