May be done seated. Purse your lips to form an 'O'. Inhale deeply, so the cheeks cave in. Shut your mouth, pressing lips back to normal.
Exhale from the nostril. This is one round. You may do up to nine rounds. Please note that since this involves mouth breathing, never to attempt this practice if you are in a polluted, dusty place or where the quality of air is suspect since that could lead to respiratory problems.
Avoid: In polluted places or if having respiratory problems.
Benefits: This is a simple version of the anti-aging cooling breathing practices called Sheetali (cooling) or Sheetkari (Whistling).
This is said to impact hunger centers in your brain, controlling emotional binging. It is a cooling practice which is an immediate de-stressor. It is a powerful anti-aging practice because it is said to tweak the parasympathetic nervous system, needed for repair and rejuvenation. Apart from that, it also works out the cheeks and the delicate region around the mouth, preventing sagging and removing fine laughter lines.
Also see: Yoga: Mudras for spiritual progress