Prana can be thought of as the energy that permeates all living things throughout the universe. It can be thought of as breath, respiration, life, vitality, and/or energy; although, it is primarily understood as the breath.
Ayana means to stretch, extend or prolong.
So, pranayama can be understood as extending or prolonging the breath.
Pranayama
Pranayama includes three main elements: inhalation; exhalation; and retention (breath holding).
- Inhalation – here, the diaphragm pushes down, and the abdomen moves out (at least initially). Inhalation stimulates the sympathetic nervous system and increases the heart rate.
- Exhalation – This is more passive and generally uses less muscular effort. It stimulates the parasympathetic nervous system and decreases the heart rate. In pranayama, exhalation is generally longer than inhalation as this promotes relaxation and calm.
- Retention – In pranayama, breath holding can be done after inhalation or exhalation and involves using the three bandhas (locks).