The focus is all on you. Your body is always seeking a structural stasis and balance. When this balance is disrupted is typically when you start feeling tension which inevitably spreads to other areas of the body. This is due to the body composition and a complex matrix of connective tissue - when one area is 'off' it creates a knock-on effect to the neighboring connective tissues to compensate. This can happen as a result of posture, misalignment, physical fitness training, injuries, surgeries, medical conditions, etc. Stress is a major component and is never just skin deep.