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breath and the next inhalation brings fresh air to all the lobes of the lungs.
The purpose of yogic breathing is to gain control over the breathing process, correct poor breathing habits and increase the oxygen intake, when necessary. Proficiency in yogic breathing means that all aspects of the breathing mechanism have come under the control of the conscious mind and can be controlled at will. This does not mean that yogic breathing should be practised at all times. During most pranayama techniques, yogic breathing is recommended. However, in pranayama it is not necessary to extend the breath into the clavicular region. The combination of abdominal and thoracic breathing is optimum and produces a comfortable rhythmic wave of inhalation and exhalation.
Advantages of yogic breathing In yogic breathing the lungs expand vertically as well as horizontally. The vertical expansion is promoted by increased diaphragmatic movement. During normal breathing the upward and downward movement of the diaphragm is approximately one centimetre, whereas in yogic breathing this movement may be as much as three to four centimetres. The sitting postures adopted during pranayama also promote greater expansion of the lungs in a vertical axis.
Normal, quiet and unconscious breathing moves half a litre (500 ml) of air into and out of the lungs (tidal volume). About a quarter of this volume (150 ml) is unused and occupies the spaces of the trachea and bronchi, which are merely air passages in which no exchange of gases occurs. Therefore, in normal breathing only a very small volume of fresh air actually enters the alveoli in the lungs with each breath. In yogic breathing a much larger quantity of air reaches the lungs and inflates more alveolar tissue. During one full inhalation up to five litres of air may be taken in. Thus, more oxygen is made available for gas exchange with the blood.
The increased vertical movement of the diaphragm also opens the alveoli of the lungs more evenly, particularly at
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