When done properly, Ujjayi (translated as “victorious”) breathing should be both energizing and relaxing. The sound of Ujjayi is created by gently constricting the opening of the throat to create some resistance to the passage of air. Gently pulling the breath in on inhalation and gently pushing the breath out on exhalation against this resistance creates a well-modulated and soothing sound—something like the sound of ocean waves rolling in and out.

You can achieve something similar lying down and cupping the ears with the hands, and tuning into the sound of your breath.  In daily life we often breathe too quickly and sometimes even through the mouth rather than the nose. This can add to our feelings of stress and anxiety. Simple techniques used in pranayama can work very quickly to slow and deepen our breathing.

Key to Ujjayi breathing is relaxation; the action of Ujjayi naturally lengthens the breath. It should feel natural and unforced. Try it at the start of your practice either sitting or lying down. Then you can bring it back into a moving practice, such as cat/cow, or bridge. Making a sound like this can help regulate and smooth out your movements, and make your yoga flow.

Bee breath (brahmari) is made simply by humming (think of a long letter M). It is relaxing and the gentle vibrations are thought to soothe, and help with anxiety.

Research is starting to back up some of these traditional techniques, and New Scientist ran the following article in January.

https://www.newscientist.com/article/mg24532640-600-how-to-breathe-your-way-to-better-memory-and-sleep/