Inhalation, Exhalation, & Retention

Pranayama includes three main elements: inhalation; exhalation; and retention (breath holding).

1. 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.
2. Exhalation – This is more passive and generally uses less muscular effort. It stimulates the parasympathetic nervous system, and so, in pranayama is generally longer than inhalation.
3. Breath holding or retention – Breath holding can be done after exhalation or inhalation. In more advanced pranayama bandhas (locks) are also included when holding the breath.