In their article “Breathing Patterns Found in Heart Attack Patients” (International Journal of Yoga Therapy, Volume 2, Number 1 / 1991) Alan Hymes, MD and Phil Nuernberger, PhD share their observation that of 153 heart attack patients surveyed, 100% (that is ALL 153 patients) were chest breathers, in whom no diaphragm expansion (let alone belly expansion) could be observed. Sure, it’s a small sample size with no control group, but 100% of 153 patients chosen randomly is still staggering.
SO, if you want a healthy heart unto old age, learn how to release your abdominal muscles and expand your belly down and forward as you enhale, and draw it gently in and up as you exhale. Better yet, work on expanding your entire belly-waist-lower back axis like a tire in all directions as you breath in, and contract it towards the center as you breath out. Yoga breathing can create a healthy habit that might save or significantly lengthen your life. No Joke.