Quick anatomy lesson
There are two nasal cavities, one behind each side of your nose and projecting into the skull. Each cavity is broadly divided into an olfactory region at the top (which gives the sense of smell) and a respiratory region below. This gives the nasal cavity four functions:
● Warm and humidify the air we breathe in.
● Remove and trap pathogens and particulates from the inspired air.
● Facilitate the sense of smell.
● Drain and clear the sinuses.
The sinuses comprise a volume of around six cubic inches.
What does the diaphragm do?
The diaphragm is a broad, flat muscle, slung front-to-back and left-to-right at the base of the ribcage. It moves downwards (and/or the ribs expand) to make space for your inhale. Breathing out is a matter of reclaiming the space (diaphragm lifts and/or ribs draw in).
It turns out that the diaphragm does considerably more than just move air. There is evidence that good breath technique will cause residual – and very healthy – movements of the brain itself. These movements are necessary to stimulate the production of fluids that bathe, surround and nourish the brain and spinal cord. This same movement stimulates the repair and regeneration of cranial and peripheral nerve fibres also. Finally, the article quoted suggests that there is a link between diaphragm health and strength and the immune response of the whole central nervous system. (It does explain though that this link is yet to be explored in research).
Why breathe through your nose?
Warming and lightly humidifying the air we breathe in makes absorption in the lungs more efficient. Also, there is evidence that the airflow itself is different: rather than a straight current of air (as from the mouth), air velocity changes and the flow becomes more circular because of the buffering provided by the nasal cavities. Some sources say that athletic performance can be enhanced because we exchange up to 18% more oxygen in each breath. Certainly, you will see a lot of web articles, written by sportsmen and women, explaining the benefits of nasal breathing for sporting performance.
We can’t ignore the filtering effect of the nose either. Air that’s breathed in through the nose is pre-processed to remove debris, delivering cleaner air to the rest of the respiratory system.
During nasal breathing, the nose releases nitric oxide (NO). NO, as a vasodilator, helps to widen blood vessels. This will improve oxygen circulation in the body, compared to breathing the same quantity of air through the mouth.
Heroes in action TV shows and films – and bad guys as well – are often depicted as breathing through their mouths. Tragedy scenes tend to be the same, with all emotion being expressed through mouth breathing. There is little in the culture around us to promote nasal breathing.
Conversely, there is evidence that ancient and more recent indigenous peoples would actively promote nose breathing. It makes sense – mouth breathing is strongly connected to snoring, and snoring would reveal position to predatory animals or rival peoples. Pressfield’s The Warrior Ethos describes a test for Spartan boys. They would have to run several miles with a mouthful of water and spit it out at the end as part of their coming-of-age rite of passage. It would prove that they were adept nose breathers – and establish this quality as an essential part of adult life.
Using these ideas in practice
Have you ever tried to flare your nostrils, like an animal? For sure, the ability to do so evolved for a reason – it allows animals to sample the air more accurately. Not everyone can flare their nostrils. If you can, try it for a few breaths: you’ll notice that you automatically take a fuller breath. You might even notice a greater sensitivity to whatever you can smell in the air. (By the way, even if you can’t flare your nostrils the first time you try, this might not mean that your body does not have the ability to do so. There are a number of muscles in the nose: if you never routinely flare your nostrils, then you may have simply forgotten how to do so. It can help to gently massage the nose: like any muscle that we don’t often use, it might be that you just need to wake the evolutionary systems up a bit.)
We’ve mentioned that the olfactory (odour-detecting) area is at the top of the nasal cavities. Try now, breathing through your nostrils, to draw the air high up into the nose. You might describe the feeling as breathing up into the eyes, or even as breathing in through the eyes. This is of course exactly how we automatically breathe when we walk into a kitchen where our favourite food is in preparation. Try this breath a few times: do you notice that the breath more naturally feeds straight into the chest when you breathe in this way?
The respiratory part of the sinus is lower in the nasal cavity. You could try now: breathing through your nostrils, bringing the breath in horizontally as if the breath would buffet into the back of your skull. Notice where your inhale goes naturally. You might find it most naturally inhabits the middle chest/ lower rib area.
It’s possible to draw the breath in with an emphasis on breathing downwards as if the air would fall straight into the body. Try this breath a few times. Notice how it lends itself naturally to an ujjayi style, and easily draws lower into the body and belly.
We will practice a simple, three-part breathing technique. It’s called “three-part” because we distinguish between a breath into the belly, the lower and mid-chest, and the upper chest. Ideally, we will be breathing through the nose.
● Begin by observing your natural inhalation and exhalation without changing anything. If you find yourself distracted by thoughts, try not to engage in the thoughts. Just notice them and then let them go, bringing your attention back to the inhales and the exhales, for a few breaths, until you feel settled.
● On each inhale, expand the belly with air as if it were a balloon. Without strain, simply fill the belly up with your breath. On each exhale, relax the belly to exhale easily through your nose.
● Repeat this deep belly breathing for about five breaths – part one.
● Then, when you feel ready: fill the belly up with air and when the belly is full, draw in more breath and let that air expand into the lower/ mid ribs. Without strain, feel the ribs expand at the front, sides and into the mid back. On the exhale, let the air go first from the rib cage, letting the ribs relax back together, and then from the belly.
● Repeat this deep breathing into the belly and rib cage for about five breaths – part two.
● Then, when you feel ready: fill the belly and lower/ mid ribs. Then top up with a little more air to fill the upper chest, all the way up to the collarbone and out into the armpits. On the exhale, let the breath go first from the upper chest, feeling the heart centre sink down, then from the rib cage, then let the air go from the belly.
● Continue at your own pace, eventually coming to let the three parts of the breath happen smoothly without pausing.
● Continue for about 10 breaths.
● [STRETCH YOURSELF] We discussed earlier breathing high into the nose, horizontally into the nose and downwards from the nose. We noted that each lends itself to a final destination for the inhale: top chest, mid-chest, belly. If the three-part breath comes easily for you, then try modulating the angle of air intake to suit the phase of the three-part inhale.
Stay healthy in the pandemic
The diaphragm is a muscle. Like any other muscle, it can be strengthened through the right kinds of exercises. We look at these exercises in some detail on the Yogafurie Academy Teacher Training course in Bristol. This results in a stronger breath capability. It does not necessarily increase lung capacity, but the breath itself is stronger regardless of lung capacity.
There is evidence that regular nasal rinsing with saline solutions greatly reduces the viral load on the respiratory system. It’s best to do this a few times a week, as a preventative treatment. It’s helpful if there is an infection, but it’s most useful at preventing infections. Hatha Yoga has long taught (for several hundred years) that students should do this, and again it features on the Yogafurie Academy Yoga and Hot Yoga teacher training course.