The role of breath is very important in the practice of Asanas or Yoga positions or yoga postures.

First we need to understand why breathing is incorporated in yoga practice. The breath is Prana or vital force. Our body requirements of oxygen or pranic energy are changing depending on our actions. If we exercise then more oxygen is required so breathing becomes faster and with force but if we are relaxing then this need of vital energy is lower and the breathing becomes relaxed and deep. Also the mental activities affect the breathing.

So for physical and mental functions, breath is very important. In Yoga practice, we integrate focus on breath during slow movements as well as while maintaining asanas or yoga poses.

If we focus on breathing, the control of breathing shifts from brain stem / medulla oblongata to cerebral cortex (evolved part of brain). The thoughts and emotions are by passed and mind can experience focus, and calm awareness. The emotional stress, random thoughts are removed. The emotions create tension in muscles, stiffness and blockages to flow of Prana. Awarenss of breath helps manage this emotional disturbances and makes the prana or energy free flowing.

Focus on breath while making movements also helps in controlling the movements, which reduce the chances of injury. The muscles work in a systematic way with greater coordination with nervous system. Neuro - muscular coordination is better.

Yoga recommends smooth, relaxed awareness of inhalation and exhalation during the practice. The mind is focused and the awareness can be concentrated on the positive thoughts.

Generally every yoga session should have a positive resolve, may it be for better physical or mental health or any other purpose. This positive resolve should be integrated with inhalation process, as the air or prana entering in to the body affects the entire body - mind complex. The exhalation can be used for relaxing and removing the stress from body - mind complex.

Ujjayi or victorious breath can also be integrated while maintaining the asanas, as this increases the psychic sensitivity and helps mind calm down faster. Also Ujjayi lowers the blood pressure so people having low blood pressure need to be careful.

Genrally the movements which involve expansion of chest should have inhalation associated with it and the movements which involve contraction of chest should have exhalation with them. The second guideline is if you are making movements against gravity then inhalation is recommended and with the gravity, exhalation is recommended. But in any case stress on heart and lungs should be kept minimum.