When someone does a physical activity to excess, they strain the muscle which was overused. This can happen to a well-trained athlete who is striving to excel, or a retired person who overdoes it working in their garden. This scenario is often seen in the “weekend warrior” athlete who sits at a desk all week, and then goes all out during the weekend with a physical activity like softball or tennis. The resultant muscle strain (mild tear) creates inflammation and pain. This strain usually occurs near the end of the muscle where it attaches to a bone or blends into its tendon. This creates a condition known as acute tendinitis. This condition could also be created if the muscle is strained from trauma. The usual treatment for acute tendinitis is to rest the area, apply ice periodically for the first 24 hours, and then to use moist heat. Rest prevents further muscle injury, the ice reduces the initial inflammation and swelling. and the moist heat circulates blood through the area to speed the healing process. Now, if you added gentle massage and stretching to this treatment plan the muscle would probably heal totally back to normal.
However, this is not what the average person usually does! They may ice once or twice and rest a bit, but most often just take an over-the-counter pain medication and continue on with their normal activities. If the strain was minor, their body may be able to heal the muscle fibers normally. Unfortunately, this is not the usual result because the injured muscle is being used instead of rested. Because of the stress on the muscle, their body heals the injured muscle fibers by binding them together with fibrotic adhesions, or scar tissue. This is done in an attempt to prevent further damage to the injured area. It is a normal protective response of their body.
Formation of scar tissue in an injured muscle causes it to become shorter and tighter than normal. This places more tension and stress on the muscle, making it easier to strain during future physical activities. If the muscle is over-stressed or re-injured further, eventually enough scar tissue will form to shorten the muscle to the degree that it can pull its attached bone out of normal alignment. The result is a joint misalignment which causes a chronic condition to develop. If a tendon receives most of the stress from the joint misalignment then chronic tendinitis develops. If a nerve is stretched or has excess pressure on it from abnormal swelling caused by the joint misalignment then a chronic neuritis condition will develop. This happens most often when the spinal vertebrae are pulled out of their normal alignment (subluxated). If the cartilage of a joint is receiving abnormally high pressure on it because of the joint misalignment, then a chronic arthritis condition will develop. Now, last but not least, if the bursae around the joint receives excess pressure and stress because of the misalignment then a chronic bursitis develops.