The first part of this event looks at noradrenalin and the reticular activating system and how through conscious breath we can effect positive change. Part two then explores the physiological effects of kumbhaka and bandhas in pranayama.

The physiology of breath holding involves respiratory, circulatory and cardiac changes including an increase in Co₂ and a decrease in O₂. These changes occur because of changes in the respiratory gases in the blood. 0₂ and Co₂ levels are involved in respiratory control, but Co₂ level is more important in holding the breath.