The fascia, which is a thin tissue covering each muscle and separates one muscle from another. All over the fascia is a lubricant which allows the muscles to move against each other without irritation. Each muscle is composed of smaller and smaller bundles of fibers. The smallest are fibriles that slide in-between each other during muscle contraction or relaxation. Each muscle component is also surrounded by fascia.
Inflammation consists of chemicals that irritate nerve endings, resulting in pain.
When these chemicals are present, nerve endings send pain messages to the brain. The type of pain may vary, as discussed earlier. The brain will send messages back to some part of the body to tell it not to function properly, partially for protection against further injury. Sometimes the messages from the area that is really hurting get mixed up with messages from other areas. So that what we think is having a problem is not really the problem.