How Deep Slow Breathing Taps into a Natural Rhythym in Our Bodies

 https://www.discovermagazine.com/health/how-slow-deep-breathing-taps-into-a-natural-rhythm-in-our-bodies

Recently I work with kechari mudra and more controlled breathing and mantras in head. Yogananda says tortoises live longer and birds shorter based on breathing speeds. If so then here we begin to find general scientific evidence for the benefits of very slow controlled breathing.