After the practice of asanas, the body is relaxed and the mind is free from all disturbances, enabling it to concentrate.
What is Pranayama?
According to Patanjali Yoga Sutras, "Regulation of breath or the control of prana is the stoppage of inhalation and exhalation, which follows after securing that steadiness of posture or seat, asana.
According to Sri Sankaracharya," Pranayama is the control of all life-forces by realizing naught but Brahman in all things as the mind, etc."
The Gita says," Others offer Prana (outgoing breath) in Apana (incoming breath) and Apana in Prana, restraining the passage of Prana and Apana, absorbed in Pranayama. Pranayama is a precious Yajna (sacrifice)."
Pranayama is the method of breath control. Proper breathing and awareness of the breath is very important. Swami Yogananda says, "Breath is the cord that ties the soul to the body". Your breathing directly affects the mental states. Breathing exercises help to control bodily functions. A regular, deep breath enables one to feel calm and an irregular breath can make you feel anxious. Yoga Breathing helps to re- charge the cells in the body and re- energizes the brain cells; thus, the body is rejuvenated.
I found a great resource for yoga breathing. The book is called The Science of Breath by Yogi Ramacharaka. I practice regularly as I don't have to do any strenuous exercises, postures or poses. I am not exactly the fittest woman on the planet, but I find practicing these breathing techniques great as a stress relief. the book can be found here if anyone else like myself is a bit out of shape!!! Lol.