Scar tissue is weak and brittle tissue, very susceptible to re-tearing and straining with certain motions and movements. When one "over-works" an area containing a build up of scar tissue, the resulting damage to the tissues further causes more build up of the weak, fibrous scar tissue.
To end the cycle, a focus on nourishing the injured tissues with a healthy supply of blood flow is critical. It is through the blood the body carries the oxygen, and nutrients needed to build new, healthy collagen.