Pranayama training is a skill to work deliberately with life energy not only in your physical body but also in mental body. "Pranayama" consists of two words, "prana" is vital energy, "yama" is moral testaments.
Pranayama is not practised as an independent technique. It’s the heart of yoga discipline that brings the result in mental and spiritual spheres. This practice has unlimited possibilities. It uses close interconnection between body and soul. You cannot learn it just by means of discussions and debates, you can master it by patient and careful efforts.
Pranayama is an exalted knowledge, a royal way to the internal freedom. Pranayama techniques allow to regulate the energy and vital strength through the control of breathing rhythm.
Pranayama is the bridge between physical and spiritual, that’s why it is the central axis of yoga.