I head to a dark area of my living room, lay down on the couch and focus on deep, fast breathing cycles, 30 reps for four rounds. (entrepreneur.com)
If you ever work with a coach they will beat you over the head with breathing cycles and techniques. (roughstrength.com)
The tone influences heart rate level at the end of breathing cycles, and is a good way to measure the body's functional flexibility, as well as estimate how often a person gets sick. (positivepsychologyprogram.com)