This is an adapted excerpt from my book The Physiology of Yoga.
Perhaps you've heard (or you've uttered) the cue "Don't forget to breathe!" during a yoga class. This class cue might be a good reminder to stay mindful of your breath but is it really so bad to hold your breath during yoga? Could breath holding during asana ever be beneficial? Should breathing be easy in every pose? Let's start with a brief look at the anatomy and physiology of the respiratory diaphragm.
The respiratory diaphragm is a double-domed sheet of skeletal muscle and a primary muscle in breathing. In addition to being a motor for inhalation, the diaphragm also contributes to creating intra-abdominal pressure along with the abdominal muscles and pelvic floor. Those three elements form a cylinder of varying intra-abdominal pressure that stabilizes our center and low back during strenuous full-body movements (Milanesi and Caregnato 2016). The degree of intra-abdominal pressure varies according to our inhalation, exhalation, and abdominal wall resistance.
The diaphragm is the roof of the abdominal cylinder and, as it presses down onto the abdomen, the side walls and pelvic floor might also engage to help stabilize the torso. It is little wonder that yogis occasionally hold their breath during a challenging asana and the teacher shouts, “Don’t forget to breathe!” But is holding the breath during yoga the cardinal sin it is painted out to be?
Powerlifters use a technique known as the Valsalva maneuver, where they inhale and brace their core, then try to exhale but stop the air with their vocal folds, which regulate airflow through the throat. Sprinters also hardly breathe during a short race. In a 100-meter race, an Olympic sprinter will often hold their breath the whole time (which is only 10 seconds) or just take small breaths of air. A breath hold can be a useful technique for a mountain climber when steady IAP is essential for a difficult move. In these examples and many others in the world of physical activity, a breath hold is an important aspect of building IAP. If those athletes were to follow that classic yoga teacher cue, “Don’t forget to breathe!” not only could their performance be negatively affected, but in the case of lifting, it could possibly be dangerous.
But yoga is not, of course, an Olympic sport — at least, not yet! Nonetheless, consider Chair Pose (Utkatasana). Because of the torso’s angle of inclination, exacerbated by lengthening the arms, which creates a very long lever from the center of mass, Chair Pose is by many standards a challenging pose, especially when held for 5 to 10 breaths. In fact, Chair Pose is very similar, biomechanically, to the sitting phase of an Olympic snatch (figure below). The Olympic lifter will probably use a breath hold, though, while the yogi will probably be cautioned to never hold their breath.
Perhaps, for a beginner who almost never lifts their arms overhead and has very poor tone in their spinal extensors, holding the breath in Utkatasana allows them to tap into a steady degree of intra-abdominal pressure for what the teacher considers five lengths of breath—and we can probably all think of a teacher whose count to five seems inordinately long.
Do you ever struggle to breathe in a backbend? Consider the diaphragm’s connection with core musculature in a backbend like Low Lunge (Añjaneyāsana). Some of the muscles being stretched include the iliopsoas, the core musculature including the rectus abdominis and transversus abdominis as well as the intercostal muscles. In a resting position, such as lying down, these structures would be relaxed and able to move freely with each breath. However, in a pose like Añjaneyāsana, the iliopsoas, core musculature, and intercostal muscles are under tension and not able to move as easily. Even the rib cage is restricted in its ability to move freely. Someone with a very mobile spine might be able to do backbends with great ease and not much change to their breathing. For someone who is tighter, their whole muscular system will be tighter, affecting the breath even more. To say that breathing should be easy for everyone in every pose would not be fair. Rather, to expect that each pose will affect the breath in a different way would be fair. For a student, hearing that it is okay if you find it challenging to breathe in a pose is much less alienating than being told that they should be able to breathe easily throughout.
While there is probably nothing wrong with encouraging your students to breathe through a pose, perhaps some compassion would be well advised instead of a shouted command of “Don’t forget to breathe!” Perhaps a better cue would be to offer this as a question rather than a commandment: “Can you continue to breathe in this pose? Can you use ujjayi to help steady your abdomen instead of a breath hold?”
Perhaps there is even a place for holding the breath in a yoga practice. As Handstand (Adho Mukha Vrksasana) is a pose that requires a very steady intra-abdominal pressure, maybe holding the breath as you lift into it might help. You can always then breathe again once you are proudly balancing. Similarly, some people, especially those who are tighter, might benefit from a breath hold while coming up into Wheel Pose (Urdhva Dhanurasana), then resuming breathing once up there.
So, should we never hold our breath in yoga? It seems, as is often the case with the human body, the best answer is probably: it depends.
Reference:
Milanesi, Rafaela, and Rita Catalina Aquino Caregnato. "Intra-abdominal pressure: an integrative review." Einstein (Sao Paulo) 14 (2016): 423-430.