The level of carbon dioxide in the body determines the length of time the breath can be held: a higher level of carbon dioxide corresponds to a longer breath hold. The table above was developed by Professor Buteyko after he had measured the breath-holding ability of literally thousands of patients and matched it to their carbon dioxide levels. The ﬁgures are consistent and show the level of carbon dioxide based on the length of the control pause.
If the control pause is eight seconds, then there is a little less than four per cent carbon dioxide in the alveoli. If the control pause is ﬁfteen seconds, the carbon dioxide is between four and four-and-a-half per cent. The aim is to increase the level of carbon dioxide to at least ﬁve-and-a-half per cent giving a control pause of forty seconds. With continuous practice of exercises, the respiratory centre will become accustomed to a higher concentration of carbon dioxide. Remember, it is the level of carbon dioxide that determines the need to breathe.
CO2 in alveoli [%]
Control pause [sec]
Low control pause
A low control pause means the body’s respiratory centre has become ﬁxed at a low level of carbon dioxide and therefore will send instructions to breathe a large volume of air in order to maintain this level. By commencing breathing exercises, an attempt is made to break this pattern by deliberately reducing the volume of air inhaled.
Regular practice of exercises and increased observation of breathing will help the respiratory centre to become ﬁxed at a higher level of carbon dioxide. Just as it took time for the respiratory centre to become accustomed to a low level of carbon dioxide, it will also take time for it to become accustomed to a new higher, and healthier, level.
The increase in CP is dependent on a variety of factors: the severity of the asthma, age, how much the breathing exercises have been practised and how much attention has been given to the breathing. The more attention to, and observation of, breathing the better.
The control pause is an accurate measure of the level of carbon dioxide in the alveoli. It therefore gives a very good indication of the state of a person’s asthma and in fact, of health generally. If the control pause is increasing then the asthma is improving. If the control pause is decreasing the individual’s asthma is getting worse.
A decreasing control pause is advance warning of an imminent attack. If the trend is for the control pause to decrease over a number of days, then it is important to take control of the condition by reducing the breathing to raise carbon dioxide levels. If it is not proving possible to increase the CP by breathing exercises, then it may be necessary to increase the level of preventative medication that has been prescribed.
A change in CP will often be noticed simply from observing reactions to various daily activities. It is possible to determine from the CP whether something is or is not good for asthma. For example, if the CP has decreased following exercise, that person has been deep breathing during the exercise, so it would be important to change the way exercise is carried out. If the CP decreased following a large steak then eating large quantities of meat may not suit that individual or it may be that too much was eaten at one sitting. If the CP consistently drops at work then stress may be a factor or a reversal to mouth breathing may have occurred while concentrating on work. The CP gives excellent feedback and enables everyone to turn detective and determine whether something is a help or a hindrance to their asthma.
To determine whether breathing exercises are being practised correctly, it is necessary to measure the CP at the start of each exercise and several times during it to ensure that overbreathing is not occurring. The aim of breathing exercises is to reduce breathing volume, which will reset the carbon dioxide threshold and therefore the CP. The breath- ing exercises are being performed correctly when the CP increases a little between each set of exercises. Breathing exercises are being performed incorrectly when the CP is decreasing between each set. The pages towards the back of this book contain detailed exercise programs.
If it is proving impossible to inﬂuence the CP, then the exercises are not being done correctly and it would probably be better to stop doing the exercises and learn how to do them properly from an experienced instructor. From week to week, there should be a noticeable improvement in the control pause. The body will become conditioned to a higher level of carbon dioxide when breath- ing exercises are practised correctly. This will be reﬂected in a higher control pause. As far as Buteyko breathing is concerned, the control pause is the most important measure- ment of an individual’s asthma.
Measuring the CP in the morning before breakfast gives the most important measurement of the state of a person’s asthma. In the depths of sleep, breathing is a subconscious activity that cannot be interfered with. For this reason, the morning CP will give a true measurement of the level of carbon dioxide. During the day, the CP will change depending on factors like eating, stress and talking, and on how the breathing changes. If the control pause is thirty seconds during the day and only ten seconds in the morning then the true control pause is ten seconds.