Students often ask me why they are supposed to breathe with their nose and belly.. Some explanations below!
"Take a moment to think about your breath: Is it deep or shallow? Slow or fast? It’s interesting that it can take a few moments to figure out our patterns of breathing, even though it’s something we’re always doing. The reason most of us can’t pinpoint what’s happening right away is because breathing happens unconsciously: It’s part of the autonomic nervous system, which tells our internal organs (like the diaphragm and lungs) to function without our conscious control. Yet unlike other functions our autonomic nervous system regulates—like digestion and circulation—breathing can also be voluntarily regulated. And when I teach patients and yoga students how to do this, it can transform their practice.
For starters, regulating the breath through a technique commonly called “belly breathing” creates more capacity to take bigger breaths. People often tell me that just 10 minutes of belly breathing seems to help their breathing feel “freer.” In turn, this leads them to tune in to the energetic center in the abdominal area, where the “belly brain” lives. Finally, there’s an energetic shift that happens when you’re able to control your breath with belly breathing. You may start to see the breath as not just air, but also as energy moving within your body. When this happens, you’re really tapping into the power of breathing.
Before learning how to belly-breathe, it helps to understand the basic anatomy of the breath. Respiration happens in two phases: inspiration (inhaling) and expiration (exhaling). Normal, restful breathing primarily uses the diaphragm, whereas exercise or exertion recruits the accessory muscles of breathing—the intercostal and upper thoracic muscles, near the ribs and chest, respectively—to further expand the chest. A full yogic breath is based on diaphragmatic, or belly, breathing, but includes intercostal and upper thoracic breathing as well.
When you inhale, your diaphragm contracts, flattening out and pressing down on the abdomen, which in turn expands the chest. At the same time, the external intercostal muscles (located between the ribs) work to lift and expand the chest by drawing the ribs upward and out, increasing the capacity for volume in the chest. A deep breath also activates the accessory muscles of breathing, including the pectorals, serratus anterior, rhomboids, and middle trapezius, which all work to expand and lift the upper chest. Finally, there are the scalene muscles, which run from the cervical spine (a.k.a. your neck) to the upper two ribs. You can feel these muscles contract by placing your fingers on either side of your neck and taking a deep, sharp inhalation. The scalene muscles work along with the diaphragm and intercostals to balance the expansion of the lower ribs by lifting the upper chest.
This increased volume in the chest not only makes room for the air coming into the lungs, it also changes the atmospheric pressure inside the lungs, creating a vacuum that actually draws air in. At the end of inhalation, the diaphragm relaxes, returning to its domelike structure, which initiates your exhale. This, along with the elastic recoil of the structures of the chest wall and contraction of the internal intercostals and accessory muscles of exhalation, raises the pressure within the thorax (the area between the neck and the abdomen), causing the air in the lungs to be expelled.
Since breathing starts with the diaphragm, I begin breathing techniques with belly breathing. Lie down, with one block under your upper back and another under your head; you can also lie over a bolster. As you inhale, actively expand your abdomen—though try not to let your chest expand until the last few seconds of your inhale. Then release and exhale, letting the abdomen fall and tightening it at the very end of your exhalation: This fully pushes your diaphragm up into its domelike shape. Repeat this cycle for three minutes, and build up to five or six minutes over time. When you feel like you’ve got the hang of this, transition into a seated position and do the same thing.
To prep your body to engage the muscles of breathing, you may want to create physical space with asana so that tight muscles don’t inhibit your effort to expand your breath. The goal of developing a deeper belly breath is to enhance your awareness of the breath circumferentially —around your entire thorax—including your sides and front and back body. To do this, practice poses that release tension from the belly, ribs, and back by stretching the thorax up and away from the pelvis. Try the poses below before your pranayama practice, and then see how much freer your breath feels and how much more in tune you become with your belly brain.
What is the “belly brain”?
This may come as a surprise, but we actually have a brain in the solar plexus (located at the pit of the stomach) that’s referred to as the “belly brain.” It is your gut feeling, and it functions largely unconsciously. In fact, most people only become aware of the belly brain in extreme situations, in which survival instincts kick in and override the “thinking brain.”
Nearly all of the practices developed to heighten awareness of the “belly brain” involve some variation of belly breathing. Beyond the calming effects of a regular belly-breathing practice, there’s a good chance you’ll also have enhanced awareness of any negative influences affecting you beyond your conscious awareness."