He Who Laughs, Lasts
“Many reflex points in the large intestine become stimulated with laughter. When the reflex points are stimulated, this has a beneficial effect on the corresponding organ.
“Abdominal laughing exercises your diaphragm. When your diaphragm moves more easily this assists the lungs to breathe deeper and more fully. When the muscles in your belly tighten, the pressure in your abdomen increases. This squeezes the arteries and veins and moves the blood.
“When the muscles release and your belly expands it creates a vaccum for the major veins and arteries, the vena cava and the aorta, which attracts blood. This mechanism acts like a second heart, and lightens the workload for your primary heart.“
From Cosmic Orbit, Mantak Chia