Understanding How You Breathe
(Adapted from Breathe Easy by Dr David Lewis)
Dr David Lewis BSc (Hons), D.Phil. C.Psychol., FISMA, FISTD
Because breathing is usually so automatic and we take it so much for granted it can be difficult to notice minor disruptions to the easy flow of air into and out of our lungs.
Consider, for instance, the way you are breathing right now.
If seated in an easy chair are you slumping comfortably in your seat?
If reading at a desk or table, are you resting your head in your hands and leaning forward over the book?
Are your legs crossed?
If so then you are reducing the efficiency with which oxygen reaches your cells and carbon dioxide is removed, because the movement of your diaphragm is being restricted. The effect of this is likely to shift you towards the left side of the arousal curve.
If you now start to breathe more rapidly and less deeply (hyperventilate) you will also change the rate at which these gasses pass into and out of your blood stream, reducing the amount of carbon dioxide present.
The Mechanisms by Which We Breathe
Although the way in which we breathe is reasonably well known, it will be helpful to examine the machinery involved in some detail since there are many subtle yet crucial aspects of this everyday activity about which many people are unaware.
A clear understanding of the basic principles of respiration and the subtle interactions between body and brain that results makes it easier to follow the practical training that follows. It will also assist in understanding of what can so easily go wrong and why these problems occur.
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The purpose of breathing is, to course, to extract oxygen from the air while removing carbon dioxide and water vapour from the body and expelling them into our surroundings.
Unlike other muscles in the body, such as the ones in our arms and legs, those involved in breathing have to contract repetitively throughout our life. Fortunately the system is extremely energy efficient, involving only between two and three percent of the body’s total expenditure while at rest. Although the rate at which we breathe increases by 15 to 20 times during strenuous exercise, the amount of energy consumed still remains below four percent.
If made to work too hard, however, these muscles can quickly become fatigued, causing us to gasp for air and leading to a rapid increase in mental and physical arousal.
While we all use our mouth when gasping for air after a strenuous run or if our nose is blocked by a cold, some people continue doing so even at rest and when their nostrils are free from congestion. This is a bad habit that must be broken if we are to breathe fully and efficiently.
From the nose air passed down the windpipe or trachea, a tube some 15 mm wide and between 10 and 12 cm long. This divides into two bronchi and these into two bronchioles, which in turn, branch into smaller structures terminating in air sacks (alveoli) within the lungs. At birth we possess around 24 million alveoli but by the time we are eight these had increased to the adult number of 300 million. If it were possible to flatten these out and place them side-by-side, they would cover an area approximately the dimensions of a tennis court.
The cone shaped lungs are made up of relatively light and porous tissues that lie more or less freely in the thoracic cavity (chest), their apex immediately beneath the shoulders, their bases resting on the diaphragm and their surfaces making contact with the ribs and spine. A double layer of membrane known as pleura surrounds each lung. Between the two layers is a fluid that bathes the surfaces and prevents friction between the lungs and the chest wall during breathing.
The right lung has three lobes but the left lung only two allowing a space for the heart that fits snugly between the two, lying mainly in a hollow in the inner left lung. To understand exactly why this is read the FREE download Why Your
Nose is Really Necessary.
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Each lobe is composed of smaller divisions called lobules. A small bronchial tube enters each lobule and divides and subdivides, its walls becoming thinner, and thinner before finally ending in the alveoli. Resembling tiny bubbles, these alveoli have walls just one cell thick that enable oxygen to pass through them and into the blood while carbon dioxide moves out of the blood and into the air.
Diagram illustrating some of the key organs making up our breathing mechanism (1) Trachea (windpipe) (2) Lungs (3) Bronchial Trees (4) Alveoli (air sacs)
For this to happen efficiently there has to be a balance between the amount of blood flowing within the tiny vessels (capillaries) that surround the alveoli and the amount of oxygen within them.
If the blood flow is insufficient the exchange of gasses cannot take place successfully, even when there is plenty of oxygen available. It is a mismatch between the amount of air present in the alveoli and the amount of blood in the capillaries that causes most of the problems associated with lung diseases.
Because blood is influenced by gravity, our upright stance means that far more flows through the lower than the upper regions of the lungs, with the least amount being present at the top (apex).
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The differences are substantial. While around a litre of blood flows through the lower lobes of the lungs, in the upper regions closer to the collar bone this declines to around one tenth of a litre.
Although the greater air flow in the upper part the lungs partly reduces this mismatch, it is still important to breathe as deeply as possible to ensure air is drawn into the lower parts of the lung where the most blood is available to transport it.
Unfortunately the majority of people fail to do so, using instead what I term
“upside down breathing” whose negative effects I describe in the FREE Bo-Tau
Download Are You An Upside Down Breather?
While the nose, wind pipe, and other tubing allows air to pass into and out of the body, the bellows that cause the air to move in the first instance is provided by muscles in the upper body, especially those between the ribs (intercostals) and by the diaphragm.
Let’s take a look at how these bones and muscles are arranged to provide the usually tireless and efficient mechanism on which our life depends. Our roughly cylindrical torso (illustrated below) comprises three separate regions:
1] The thorax in which our lungs and heart are located.
2] The abdomen lying directly beneath it and separated from it by the diaphragm, containing digestive organs.
3] The pelvis, which extends from the hipbones to the bottom of the torso and contains organs responsible for getting rid of waste and reproduction.
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The thirty-three vertebrae that make up the spine provide both the supporting structure and the framework around which the other tissues and organs are grouped.
These vertebral bones are separated from one another by spongy shock absorbers known as vertebral discs.
X-Ray depicting collarbones, ribs and lungs
A skeleton superimposed over a living human torso indicates the relative positions of the rib cage, collarbones and spine. At the front some, but not all, of the ribs are attached to the sternum or breast bone that terminates in the xiphoid process. (Still taken from the Bo-Tau Home Training DVD)
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Pairs of ribs are attached to the twelve vertebrae that support the thorax.
Lying parallel to one another on each side of the chest, they curve forward and downward, with the first ten joined at the mid-line to the breastbone (sternum) to form a strong yet flexible cage. Because they increase in length and curvature from the top of the chest to the bottom the lower part of this ribcage is also the widest.
Attached to the lower ribs, the breastbone and spine is the diaphragm, separating chest and abdominal cavities. As we breathe in and out, the rise and fall of our chest and movement of the abdomen is produced by two sets of muscles known as the primary and accessory muscles of inhalation.
Primary muscles are used only during quiet breathing at rest, while the accessory muscles come into action whenever we need to breathe more rapidly, for such as during vigorous exercise. Accessory muscles may, however, be brought into use inappropriately as the result either of a physical problem, such a chronic obstructive lung disease, or a psychological one, such as a panic attack – that results in rapid, shallow, breathing (hyperventilation).
During relaxed breathing the primary muscles contract in a coordinated fashion causing the diaphragm to move down and outwards as the ribs move upward and out. This lowers the pressure inside the thorax causing air to flow into the lungs.
These muscles then relax allowing the breath to be expelled due to the elastic recoil of the lungs. In theory there is nothing to prevent one inhaling so deeply and inflating the lungs to such an extent that the delicate alveoli burst under the pressure.
In practice, however, this can never happen.
Once the lungs have expanded to a critical point a reflex response inhibits inspiration and causes us to breathe out again. Conversely, deflating the lungs triggers another reflex that obliges us to take a breath.
The Primary Breathing Muscles
Three primary muscles are involved when we take a relaxed breath; the most important of which is the diaphragm, the others being the parasternal and scalenes.
Because the diaphragm is essential for deep, life enhancing, breath work I shall describe its structure and function in more detail. This large yet thin, double dome-shaped, muscle fits inside our chest like a parachute, separating the lungs and the heart within the chest from the organs of digestion such as the stomach, liver and intestines, within the abdomen.
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At the top of the dome the diaphragm is a central tendon, flattened somewhat to accommodate the heart that rests directly above it and is angled towards the left of the body. Radiating from the tendon are fibres that attach the diaphragm to the inner surfaces of the body. Frontally these fibres connect with the inner surface of a small structure at the end of your sternum known as the xiphoid process.
At the sides they are attached to the seventh through to the twelfth ribs and at the spine to the first through to the fourth lumber vertebrae.
When we breathe deeply and correctly, the diaphragm contracts forcing the guts downward and forward while simultaneously pulling the ribs upwards and outwards in what is sometimes described as a bucket-handle motion. At the same time the parasternal muscles, which are attached to the breastbone and run between each rib, also contract increasing the size of the chest cavity. The scalene muscles, lying on each side the neck, perform a similar action by raising the first and second rib while also helping to stabilise the chest wall.
This creates a larger cavity inside the chest as a result of which the pressure inside the body falls below that of the surrounding atmosphere causing air to flow into the lungs and restore the balance.
When the diaphragm relaxes and billows upward inside the chest the air inside our lungs is compressed and flows out again during an exhalation.
At the same time, as pressure within the chest falls, both the diaphragm and the parasternal muscles relax while the rib cage returns to its previous shape.
During quiet breathing this is a passive process requiring no muscular effort, made possible by the fact that our lungs and chest walls are elastic and, like a rubber band, tend to return to their starting position once the tension created during the inhalation is released.
The process is, however, assisted by four abdominal muscles – the rectus abdominis , the external and internal obliques , and the transverses abdominis . All these muscles have attachments to the lower ribs so that contracting them decreases the size of the rib cage so assisting in exhalation.
The first group of muscles form the so-called “six pack” that man who work out regularly like to flaunt on the beach.
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The ‘manly’ six-pack – good for self-image but less good for breathing
Unfortunately, when these frontal muscles are stronger than the others an imbalance is created that undermine what is termed “core stability” and this inhibits healthy breathing.
During deep, health enhancing, breathing the diaphragm performs between
70% and 80% of all the work necessary, leaving the remainder to be done by the secondary respiratory muscles.
When we breathe in this way a stable triangle is formed, with its base extending across the centre of the body. This type of breathing creates a subjective feeling of being grounded and more in touch with our “gut feelings.”
Deep diaphragmatic breathing (DDB) which you will learn in the Bo-Tau
Home Training Programme will also help protect and nourish your spine.
Since, as we have seen, the diaphragm attaches along the front of the lumber vertebrae when it is able to move freely and easily this powerful muscle not only helps to stabilise the spine but also helps prevent bone degeneration and arthritic condition by providing traction to the vertebral column.
It also safeguards you against the agony of a trapped nerve while keeping the spongy the intervertebral discs plump and healthy. Because, after the age of about twenty, these discs lack their own direct blood supply their only way of remaining moist is by absorbing fluid from the surrounding tissues, something that only occurs during movement.
In addition regular, rhythmic movement of the diaphragm gives all the organs of digestion, reproduction and excretion an excellent workout.
As Donna Farhi graphically puts it in The Breathing Book : “When the diaphragm moves in the luxurious expansions that mark full breathing, all these organs are massaged, rolled, churned and bathed in new blood, fluids and oxygen…Breathing stimulates all of the body to work better and this is why it has such a profound effect on our sense of well-being”. (p.53)
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Without this massage the organs of digestion, the stomach, liver, spleen, intestines, colon and bladder, can become sluggish. Toxins are removed less efficiently there is a reduction in the amounts of oxygen received by these organs.
Sadly for good health and maximum vitality this is not the way the majority of us tend to breathe.
A full description of the mechanisms of by which we breathe and how the ways we breathe can positively or negatively affect our health can be found on the
Bo-Tau Home Training Programme DVDs
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