The intimate relationship between the emotions and posture, and the mechanical use of the body, should be emphasized. Insofar as the soft tissues are concerned the relationship is a palpable one. Anyone who wishes to demonstrate this connection to themselves, need only sit for a moment or two and imagine an emotion, such as anger or disappointment, or any other strong feeling. Allow yourself to think and feel these emotions for some seconds, and become aware of the subtle, but noticeable, change which begins to occur in the muscles of the abdomen, the jaw, the shoulders, etc. Imagine then the effect of holding such emotions, not for a minute or two, but for months or years. The changes in the tissues would be dramatic, and would influence all function, and certainly posture.

-Leon Chaitow, Soft-Tissue Manipulation