As yogis have known for centuries—and as medical science is beginning to discover—the breath has amazing recuperative powers. By controlling the breath (a practice called Pranayama), the yogis found, they could alter their state of mind. The three pranayama practices described here primarily create their effects by slowing and regularizing the breath. This engages what scientists call the parasympathetic nervous system, a complex biological mechanism that calms and soothes us.
How does slower breathing help? In stressful times, we typically breathe too rapidly. This leads to a buildup of oxygen in the bloodstream and a corresponding decrease in the relative amount of carbon dioxide, which in turn upsets the ideal acid-alkaline balance—the pH level—of the blood. This condition, known as respiratory alkalosis, can result in muscle twitching, nausea, irritability, lightheadedness, confusion, and anxiety.
In contrast, slowing the breath raises the carbon dioxide level in the blood, which nudges the pH level back to a less alkaline state. As the blood’s pH changes, the parasympathetic nervous system calms us in a variety of ways, including telling the vagus nerve to secrete acetylcholine, a substance that lowers the heart rate.
As with any treatment, the breathing remedy must be administered intelligently and judiciously to be fully effective. Each condition responds best to its own special breath. To calm anxiety, for example, you can purposely lengthen your exhalations; to alleviate dullness and fatigue, you can lengthen your inhalations. And to lift yourself out of an emotional pit, it’s most effective to equalize the lengths of your inhalations and exhalations.
You’ll probably notice that watching the breath immediately initiates a chain of changes in it. First, it slows down. As it slows, its ordinarily rather ragged movements smooth out. And as the breath smoothes out, the space it occupies in the body increases.
When we breathe, most of us usually expand only a limited portion of the torso, generally in the front around the lower ribs and upper belly. Often, our breathing is restricted and shallow; ideally, it should be deep and full, so each breath cycle expands and contracts the height, width, and depth of the whole torso.
To experiment with consciously expanding your breath, sit in a chair with your spine erect—or, better yet, lie on your back on the floor. Put your fingertips lightly on your lower belly, just above the pubic bone, and try to direct a few inhalations into this space, expanding the belly each time. Once you can do this, move your fingertips to the spaces below your collarbones, placing your pinkie tips on the sides of the sternum and splaying the rest of your fingers out to the sides.
Then, for a few inhalations, see if you can gently expand these spaces. Be careful to keep your throat as soft as possible as you do this, because there’s a counterproductive tendency to tense it as you inhale into the upper chest.
Once you can move the breath into the lower belly and upper chest, try to awaken your entire back torso, an area that is terra incognita for many people. As much as you can, breathe into your back body, feeling how it balloons and then deflates with each breath cycle. Once you can feel this, experiment with filling all of your newfound spaces with every breath.
Sometimes just watching and expanding your breath for several minutes can have a surprisingly positive influence on your energy level or mood. You can multiply this effect significantly by using pranayama—breathing exercises tailored to have an effect on specific moods and conditions. Based on knowledge cultivated and refined by the yogis over thousands of years, these exercises intentionally alter the speed, rhythm, and space of the breath.
Excerpts from Yoga Journal Article Inhale, Exhale, Relax and Energize by Richard Rosen