Channel Purification: The First Step in Pranayama


We don’t usually give much thought to the fact that the nose is divided into right and left nostrils. Instead, we tend to think of the nose as a single passageway. But in the practice of yoga, the fact that there are two nostrils is an important detail of human anatomy. Yogis regard the nostrils not merely as passive entranceways for air but as connecting points leading inward to a vast system of energy. The first step in the practice of pranayama is an exercise for unblocking and balancing the flow of this vital energy. This practice is called nadi shodhanam—channel purification.


The division of the nose into two channels is a good example of the architectural dictum “Form follows function.” Yoga texts, both ancient and modern, remind us that the two nostrils have different energy potentials—the left nostril gives the incoming air a negative charge as it enters the body while the right nostril gives it a positive charge.

This corresponds to polarities in the experience of energy at all levels of human functioning. Our moods “run hot or cold.” We may be “hot on the trail” of an idea or our thoughts may be “cold and calculating.” We even describe ourselves as hot- or cold-blooded. These pairs of opposites form a backdrop for our experience of the world. As one poet reminds us, “We don’t see things as they are, we see them as we are.”

Differences in the energy of the two nostrils are beautifully symbolized in yoga literature. Energy passing through the right nostril is said to travel in the “solar” channel, pingala. Energy passing through the left nostril is described as traveling along a “lunar” channel, ida. Sun and moon, male and female, active and receptive, rational and intuitive, contracting and relaxing, hot and cool, rigid and fluid—these and other pairs of opposites are captured in the archetypes of the two channels of breath.

The poles of experience may be as easy to describe as the nose on your face, but complexity, not simplicity, is the rule here. Ida and pingala are but two of more than 72,000 channels, called nadis in Sanskrit, that direct the flow of vital energy. The origin of many of these nadis is the solar plexus, from which energy is said to radiate throughout the body. Depending on our thoughts, desires, actions, and habits, this energy manifests in myriad patterns within us.

Ida and pingala are but two of more than 72,000 channels, called nadis in Sanskrit, that direct the flow of vital energy.

Ida and pingala twine around the sushumna nadi, the primary channel of spiritual awakening, which lies along the central axis of the spine. When dormant energy is awakened and begins to travel upward along this nadi, awareness itself expands. The ascent of sushumna is a reality to highly accomplished yogis and a powerful spiritual metaphor for less accomplished practitioners. Attachment to the objects of sense experience prevents this awakening, blocking the balanced flow of energy in the body, while faithful practice of yoga disciplines and the cultivation of dispassion toward sense experience loosens these blocks.

Breathing practices have a direct effect on the flow of energy in the nadis. Through pranayama, energy can be aroused or calmed, used to produce heat or inner cooling, and directed for the restoration of health and for longevity. As in so many other practices of yoga, however, the initial focus of pranayama is purification. It is the goal of every beginning aspirant to cleanse the nadis of impurities that might otherwise disturb concentration and impede the natural movement of prana.

Channel purification, or nadi shodhanam, is the first formal pranayama practice given in yoga. It is a cleansing practice. It is also called alternate nostril breathing because it involves breathing through one nostril at a time. In addition to opening the flow of energy along the nadis, this practice is an excellent preparation for meditation. It calms, purifies, and strengthens the nervous system, and leads to establishing sushumna breathing, the condition in which the sensation of the breath flowing through the two nostrils is united in awareness into one central stream.

Guidelines for Practice

If possible, it is best to find a qualified teacher who can demonstrate channel purification. This will allow you to observe the pace and serenity of the breath before practicing on your own. You need to pay attention to all aspects of the technique, including the steadiness of the spine in the sitting posture, the quality of your diaphragmatic breathing, the skillful manipulation of the nostrils as the stream of breath is alternated from one nostril to the other, the degree that attention is maintained during the practice, and the internal and external setting. This list may seem overwhelming, but the practice will soon be comfortable and nearly effortless if you give it your respectful attention.

It is best to do channel purification two or three times a day. The general guidelines for all yoga practices apply: practice on a light stomach, empty the bladder beforehand, and stay within your comfortable capacity. When channel purification forms part of a complete yoga practice session, it is done just after hatha postures and prior to meditation. If it is not followed immediately by meditation, you should allow some time, perhaps five minutes, to maintain and enjoy the tranquil state of mind it produces.

To fully integrate the benefits of channel purification, it is important to cultivate a yogic lifestyle—neither overindulgent nor too ascetic. The mind needs to be alert, not fatigued. Do not practice when you have a headache or fever, or when anxiety makes you restless and agitated. Those with a seizure disorder should not practice alternate nostril breathing at all. If you have any of these conditions, practice relaxation in the corpse posture to rest the mind.

To fully integrate the benefits of channel purification, it is important to cultivate a yogic lifestyle—neither overindulgent nor too ascetic.

In addition to these general suggestions, there are three essential guidelines for practicing channel purification:

1. Sit with your head, neck, and trunk straight throughout the entire practice. If the practice is done with a bent spine, it can result in disruption of the nervous system and increased mental and physical tension. (Swami Sivananda went so far as to equate practicing with a curved spine to bombarding the spine with a jackhammer.) Sit in any comfortable meditation posture, including sitting erect in a chair with a flat seat.

2. Breathe diaphragmatically with no pauses. It is easy to neglect the natural, diaphragmatic movement of the breath while concentrating on the manipulation of the nostrils. Don’t let this happen. Keep the breath deep, smooth, and relaxed. With practice the length of the breath will gradually increase.

3. Close off the nostrils lightly. It is common to see students focusing so intently on manipulating the nostrils that they bend the nose to the side by applying too much pressure on the nostrils with the finger and thumb. The nose should not be distorted nor should the balanced alignment of the head and neck be altered.

The nostril used to begin the practice is commonly determined by the time of day. The maxim “right at night” (and, therefore left in the morning) is an easy way to remember. Begin your evening practice on the right side. In the morning, begin with the left nostril. If you practice at midday, begin by exhaling through the nostril which is the least open (the passive nostril). If the nostrils are flowing equally, which is less common than you might expect, you may start on either side.

Yoga breathing exercises generally begin with an exhalation. This is both symbolic and practical. It reminds us that before we are ready to receive energy from the universe we must prepare ourselves by emptying wastes and impurities—including egoism. Practically speaking, the exhalation is a cleansing breath; it readies the lungs and nervous system for the inhalation, which is the potent breath in channel purification.

The Technique

There are a number of patterns for alternating the breath in the nostrils. For now, we’ll stick to one of the best methods for getting started. Because this practice requires only a few minutes to complete, it is an excellent beginning technique; advancing students can expand it and incorporate longer variations.

1. Sit with your head, neck, and trunk in a straight line. Take time to establish a sense of balance and stillness in your posture. Let your body relax.

2. Become aware of your breathing, and allow your breath to become deep and smooth. Let it flow without pause. Feel the upper abdomen, sides, and lower back expand with inhalation and contract with exhalation. (In sitting postures there is also a very modest expansion of the chest wall, but diaphragmatic contraction and expansion predominates and should be clearly felt.)

3. Focus on the breath touching the nostrils. Feel the warm touch of exhalation and the cool touch of inhalation. Establish a steady awareness of the flow of breath—permit no breaks in your breathing and no breaks in your awareness.

4. Maintaining your posture and your diaphragmatic breathing, bring your right hand up to the nose. Arrange your right hand in vishnu mudra, a position in which the index and middle fingers are either curled to touch the base of the thumb or rested lightly on the area between the eyebrows. The thumb closes the right nostril, and the ring finger closes the left. Press lightly on the side of the nostril you are closing—just below the point where the bony part of the nose begins.

We’ll begin with an evening practice. Take three breaths, out and in, through the right nostril; switch to the left nostril and take three breaths, out and in; then take three breaths out and in through both nostrils. These nine breaths complete one round of channel purification. Keep the breaths silent, smooth, and equal in length. Do not hold the breath. (If the nostrils are too congested for practice, you will want to learn how to do the nasal wash to clean them.) Reverse this pattern for morning practice—begin on the left side, then go to the right, and then breathe with both nostrils.

Now lower your hand and bring your attention to the breath flowing in the nostril that feels most open. Relax and attend to the sensation there for a number of breaths. Next, shift your attention to the breath in the more passive nostril. Keep your focus there for some time (you may find that the nostril opens as you concentrate). Simply attend to the flow of the breath. Finally, merge these two streams in your awareness, sensing the breath as if it is flowing in one central stream. It is as if the mind, breath, and energy become one. Let your focus on the breath become relaxed and one-pointed. This experience of feeling the flow of breath in a single stream is the beginning of establishing sushumna.

Your focusing power will increase gradually with daily practice, and soon your attention will rest wherever it is placed.

Of course, the mind often wanders, becomes identified with some other thought process, and loses its focus. Part of the challenge of pranayama is to learn to focus on the breath, allowing thoughts to come and go without distracting you. Your focusing power will increase gradually with daily practice, and soon your attention will rest wherever it is placed.

Those experienced with the practice have noted that channel purification has two important effects on meditation: it turns the mind inward and it seems to provide energy for focusing the mind. With repetition the fingers do their work automatically, and nothing impedes the joy of concentration.

About the Teacher

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Rolf Sovik
President and Spiritual Director of the Himalayan Institute and a clinical psychologist in private practice,... Read more