I was a dancer and my posture ‘technically’ excellent, BUT that posture was wrong for the unique composition of my body. On top of this, I was tensed up all the time, I was indeed ‘chest breathing’ and the conditions I have been aware of since my teens were made worse by the extreme physical activity (in the long-term). Now 50, I suffer with multiple chronic pain and fatigue issues and can barely exercise at all. It’s taken me years to learn to relax my body, breath fully/properly and truly understand what kind of posture/movement is good for my body.