Learn the Secret. BodyFlex breathing is a specific kind of deep breathing exercise combined with isotonic (equal tension) and isometric (equal measurements) stretching positions. It's so easy to learn the secret to BodyFlex breathing, virtually anyone can do it. Normally, we breath very shallow breaths. We've learned to live below the minimum for so long that we don't even know what it's like to feel energized and feel good. You're going to notice some big results right away when you practice the BodyFlex deep breathing techniques.