Book review: Oxygen Advantage by Patrick McKeown
In his book, The Oxygen Advantage, Patrick McKeown explains the science behind the need to breathe efficiently through the nose not the mouth to improve both fitness, wellness, and performance. Based on the Butekyo method of breathing which the author claims have helped many patients with asthma and other breathing conditions, McKeown has developed the techniques to address issues around over breathing and other habits we develop that have an impact on health and wellbeing.
The benefits of good nutrition and hydration are well known and accepted and yet humans can last for several days without food and water. However, we can’t survive for many minutes without oxygen and yet we focus little on the way in which we breathe and the rate at which we do it.
The author emphasises how breathing should be a natural and involuntary process but is adversely affected by modern day sedentary lifestyles, stress, poor diets, being overweight and lack of fitness. He examines several different ancient cultures and meditation practises which have long since adopted nasal breathing and diaphragmatic breathing highlighting the benefits gained. In his words “we are born to breathe through our nose and eat with our mouth”.
Breathing at rest sets the pattern for breathing during exercise. So, unless we learn to breathe efficiently at rest it will adversely affect our fitness capacity. Breathlessness limits exercise capacity before muscle fatigue.
In many schools of thought, taking large deep breaths is advocated for relaxation and yet ironically over breathing either by taking too many breaths per minute or breathing too deeply can signal a chain reaction in the body that can trigger our fight flight fright response and spiral anxiety levels up, not down. Signs of chronic over breathing include mouth breathing when at rest, walking or sleeping and sighing or audible breathing. Chronic over breathing has been linked to loss of wellness, fitness and performance as well as potentially contributing to many diseases such as anxiety, asthma, fatigue, sleep disorders, heart problems and weight gain.
The rate and volume of breathing is determined by receptors in the respiratory centre in the brain which monitor concentration of blood pH, oxygen and carbon dioxide. The amount of oxygen we can use in the body is not only dependent upon the level of oxygen but also by the level of carbon dioxide in the blood. Haemoglobin releases oxygen to be metabolised by the body, but only in the presence of carbon dioxide. This is called the Bohr Effect. Correct breathing maintains the right balance of carbon dioxide in the body. During exercise, consumption of oxygen increases, and carbon dioxide levels increase making blood pH levels more acidic. The respiratory centre is activated to increasing breathing.
Oxygen is the fuel for muscles and carbon dioxide holds the key for oxygen to reach our muscles. Usually, our red blood cells are saturated with between 95% and 99% oxygen, therefore breathing more cannot force more oxygen in, however, over breathing can rid the body of too much carbon dioxide. This means haemoglobin holds on to oxygen and narrows the blood vessels which restricts flow to the muscles and brain. Over time it makes the body more sensitive to carbon dioxide and increases breathing rate, however, with exercise training, athletes can teach receptors to become less sensitive and become more resistant to fluctuating carbon dioxide levels making some athletes up to 60% less breathless with exercise than non-athletes.
In response to a greater need for oxygen or increased carbon dioxide, the kidneys increase production of a hormone that promotes the formation of red blood cells called EPO and causes the spleen to contract which releases more red blood cells and increases haemoglobin into the blood circulation. EPO has been used in the past for illegal performance enhancement and is the hormone that is linked to improvements in performance from altitude training. However, McKeown also reports an increase in EPO by 24% after breath-holding exercises and an increase in oxygen carrying capacity of the body which he suggests might mean that the benefits gained by altitude training could be gained anywhere.
Nasal breathing v mouth breathing
When we breathe efficiently, McKeown suggests that the air should enter via the nasal passages which are designed to both warm and humidify the air as it enters the body and filter out unwanted dust or bacteria. Deep breathing should be deep into the lungs where there is greater blood flow for gas exchange but should not include a rising of the chest.
The gas nitric oxide (NO) is found in the lining of blood vessels and nasal airways in humans. When we breathe in through the nose, NO will follow the flow of air into the lower part of the lungs. NO sends a signal for the blood vessels to relax and dilate encouraging better oxygen transfer. If there’s too little nitric oxide, blood vessels constrict, and therefore blood pressure rises. NO has been linked to preventing the build-up of plaque in the blood vessels and in helping to prevent blood clotting. McKeown reports a link to high blood pressure, high cholesterol, nasal polyps, impotence, and other cardiovascular and respiratory conditions in mouth breathers who miss this vital release of NO found in nasal breathing.
It is possible to increase levels of nitric oxide by nasal breathing during gentle exercise and by eating foods rich in nitrates such as beet juice, fish, green veg, red wine, oatmeal, dark chocolate and limiting processed foods and meats. There is a link between processed foods which tend to be more acidic versus the alkaline diet of our ancestors.
Benefits of nasal breathing:
- Reduced breathlessness
- Increased EPO and therefore red blood cells
- Improved sleep
- Improved fitness and endurance
- Improved cardiovascular health – reduced blood pressure
- Greater energy
- Reduced lactic acid
Individuals who mouth breath either by day or night or those who talk a lot when awake such as teachers often feel exhausted despite sleeping due to an increased rate of breathing. Mouth breathers tend to have to chew with their mouth open as they can’t eat and breathe at the same time.
Our ancestors had wider jaws and straight teeth due in part to the resting position of the tongue just behind the teeth on the top palate. Prolonged over breathing, thumb sucking and mouth breathing can change alignment of the jaw and teeth. The face may become narrower, and the jaw is set back affecting air entry often requiring orthodontic work. It may cause greater dental decay, bad breath, snoring, a dry mouth, and dehydration so there are many good reasons to switch to nasal breathing.
Many elite athletes nose breath and have wide facial features with broad upper airways airway entry.
How to test breathing efficiency
Body oxygen level test (BOLT)
The BOLT test is a simple, accurate and safe method described in the book to assess the relative breathing volume during rest and the onset of breathlessness during physical exercise. It claims to tests your carbon dioxide tolerance. A low BOLT score suggests poor tolerance to high levels of carbon dioxide and higher sensitivity to carbon dioxide levels and higher likelihood of breathlessness during exercise. The score is determined by the length of time before the first urge to breathe increases enough to initiate inspiration again. It is not a test of willpower or a measure of capacity to hold breath
- Rest x10 minutes – best done first thing in am on waking
- Take a small silent breath in and out through nose
- Hold your nose with fingers to prevent air from entering your lungs.
- Use a timer to count the number of seconds until first definite desire to breathe in or you may feel muscles in neck or stomach start to twitch
- Release nose and breathe in through nose – this should be a calm breath. If you are not able to breath easily at the end of the test you have held your breath too long.
- Assess length of hold
A BOLT score of less than 10 seconds is likely to impact wellness.
A common starting BOLT score for an individual who exercises regularly at a moderate intensity will be approximately 20 seconds.
You should aim for a BOLT score of 40 seconds
Each time that your BOLT score increases by five seconds, you will feel better, with more energy and reduced breathlessness during physical exercise.
Contraindications to breath holding
- Pregnancy
- Illness
- After eating
Steps to increasing breathing efficiency
- Breathe through the nose – keep your mouth shut
- Tape your mouth shut (if safe to do so!) at night to improve nasal breathing when sleeping
- Reduce breathing volume to reduce breathing rate
- Counteract the urge to sigh – swallow
- Try not to take a big breath when yawning
- Try to speak slower if you can hear yourself breathing when speaking. Gently breathe between sentences
- Clear your nose with a nasal unblocking exercise
- Breath light to breathe right at rest and gradually during walking before introducing in higher intensity exercise
- Incorporate controlled breath holding to simulate the benefits of training at altitude. Only hold your breath until there is a mild hunger for air and ensure you can revert back to normal breathing gently through the nose within 2 breaths. If you try to hold your breath too long initially it is counterproductive.
This information is an interpretation of the book The Oxygen Advantage and does not substitute proper breathing re-education training. People interested should read the book or visit the website for courses and further information www.oxygenadvantage.com
