I have learned about functional breathing through the book The oxygen advantage by Patrick McKeown. There are several aspects of functional breathing that are really interesting. It is claimed (is this true?) that most people ‘learn’ how to do upper chest breathing by going to school, sitting at desks all day, and being anxious often. Upper chest breathing is usually shallow and rapid (this is easy to observe in yourself), and you use the muscles of neck and shoulders to breathe in and out, leading to tension in neck and shoulders. Basically more people habitually use the wrong breathing muscles, using the upper chest, shoulders and neck muscles more than the ribcage and diaphragm. There is an important emotional effect of this type of breathing, we breathe high in our chest when we are anxious, and breathing this way ‘makes’ us feel anxious. I think it can be very beneficial for a lot of people who suffer from tightness in neck and shoulders, tension headaches and migraines, and anxiety to observe how they breathe. A lot can be done simply by training the body to breathe more functionally, using the muscles that are made for breathing, and breathing through the nose (remember ‘the nose is for breathing, the mouth is for eating’).

Another aspect of a habitual breathing pattern is chronic overbreathing or hyperventilating, which basically means taking in larger volumes of air than the body requires. We over breathe through breathing through the mouth, sighing a lot, talking, breathing hard, upper chest breathe. When we breathe in more than we need, too much CO2 is removed from the body. This overbreathing is not a problem if it happens during a short time, but when we do it chronically, a biochemical change in the body happens that results in an increased sensitivity or lower tolerance to CO2.  Unfortunately this is a vicious circle, with the lower set point for CO2 breathing volumes remaining more than normal, while the receptors in the brain continuously stimulate breathing in order to get rid of the CO2 which is perceived to be in excess. Our body breathes in a way that is against our interests. Some symptoms that are linked to chronic overbreathing: nasal congestion,tightening of the airways, fatigue, dizziness and lightheadedness and it leads to (or is linked to) conditions such as anxiety, asthma, fatigue, insomnia. The reason is that the amount of oxygen your muscles and tissues have access to is dependent on the amount of CO2 in your blood. Due to the Bohr effect, CO2 is the thing that determines how easy it is for oxyhemoglobin to release or hold on to the oxygen. When we breathe correctly, our breath is quiet, controlled and rhythmic and we have sufficient CO2 in our blood to allow the availability of oxygen for our muscles and tissues to use. If we overbreathe, our breathing is heavy, more intense and erratic and we exhale too much CO2, leaving our body gasping for oxygen. The problem is not a lack of oxygen in the blood, but that not enough oxygen is being released to the tissues. 

CO2 in the blood also affects the dilation of the smooth muscle in the walls of the airways and blood vessels. Overbreathing can reduce blood flow, especially in the brain (see the effects of breathwork on our physiology), which is why people can feel dizzy after a few big breaths. Mouth breathing while sleeping and excessive talking (when we generally overbreathe) can thus lead to grogginess and fatigue (due to breathing increasing without the physical need for it such as during physical exercise). These principles are the explanation of why people who hyperventilate (usually in a panic attack), are told to breathe in a bag, to breathe in more CO2 and counter the effects of overbreathing. Another way would be to avoid overbreathing all together and train ourselves to breathe ‘functionally’. 

How can we do this?

→ Stop the loss of CO2

  • Only breathe through the nose, during sleep and when awake
  • Tape your mouth to become aware how much you mouth breathe
  • Stop sighing
  • Avoid taking big breaths when talking or yawning
  • Observe your breath

→ Improve your tolerance for CO2

It is possible to train yourself to improve your tolerance for CO2, for example by doing breath holds and other types of exercises, such as breathing less than you feel you need to during physical exercise.

Another reason why it’s better to adapt light breathing habits is the production of the gas NO (nitric oxide) in our sinus cavities. By nose breathing calmly, the air we breathe in and out has more chance to hang out in our sinuses and get in contact with nitric oxide synthase to produce NO. Curiously humming increases the production of NO in our sinuses as well. Unfortunately we can’t blindly say ‘NO is good for you’, the role of NO in our physiology is extremely complicated with lots of seemingly conflicting results in the research, and at this point it’s not clear to me if the NO they talk about in some of the depression research articles is the NO that we breathe in through the lungs. There is some promising research being done on NO as a sterilising gas and its effects on viruses such as covid-19. Basically, when you’re in the presence of other people in closed spaces, it’s safer to breathe through your nose. Not only does the nose have a filtration system in place to get rid of unwanted particles, but by holding your breath, you also create this sterilising gas inside your nose. 

This is just a summary of all the information in the book The oxygen advantage, which is mostly written for fitness people to improve performance, but there is so much really interesting information in it that I think can be beneficial to know, especially when working with people who suffer from chronic stress, or being such person.