No matter what anybody else tells you, yogic breathing typically occurs through the nose, during both inhalation and exhalation. For traditional yogis and yoginis, the mouth is meant for eating and the nose for breathing. Here are at least three good reasons for breathing through the nose:
It slows the breath because you’re breathing through two small openings instead of the one big opening in your mouth, and slow is good in Yoga.
The air is hygienically filtered and warmed by the nasal passages. Even the purest air contains, at the least, dust particles and, at the worst, all the toxic pollutants of a metropolis.
According to traditional Yoga, nasal breathing stimulates the subtle energy center — the so-called ajna-cakra (pronounced ah-gyah-chuk-rah) located near sinuses in the spot between the eyebrows. This very important location is the meeting place of the left (cooling) and the right (heating) currents of vital energy (prana) that act directly on the nervous and endocrine systems.
Folk wisdom teaches that every rule has its exception, which is definitely the case with the yogic rule of breathing through the nose. A few classical yogic techniques for breath control require you to breathe through the mouth.
What if I can’t breathe through my nose?
Some folks suffer from various physiological conditions that prevent them from breathing through their noses. Of course, Yoga is flexible. If you have difficulty breathing when lying down, try sitting up. The time of day can also make a difference in your ability to breathe. For example, you may be more congested or exposed to more allergens in the morning than in the afternoon.
If you’re still not sure how to settle on a comfortable breathing method, first try inhaling through your nose and exhaling through your mouth. Failing this, just breathe through your mouth and don’t worry for now; worry is always counterproductive.
What about breathing through my nose all the time?
Many Americans participate in more than one kind of physical activity or exercise discipline. Each has its own guidelines and rules for breathing, which you should follow. For example, the majority of aerobic activities — running, walking, weight lifting, and so on — recommend that you inhale through the nose and exhale through the mouth. The reason: You need to move a lot of air quickly in and out of your lungs.
In the beginning, save yogic breathing for your Yoga exercises. Later, when you become more skillful at it, you may want to adopt nasal breathing during all normal activities. You can then benefit from its calming and hygienic effects throughout the day.