Tight contracted fascia weakens the muscles that it surrounds because instead of utilizing muscles to get the job done and be strengthened, the fascia is already primed and tight (just like the compression sleeve of a basketball player to help with a free-throw). Along with the muscles not needing to work, the nerves of those muscles are compressed and therefore are unable to send signals to the muscles, creating a double weakness. Muscles get tight. When fascia gets unnecessarily tight, range of motion in the joints becomes limited and therefore this is where stretching comes in. Stretching is so important for keeping your body flexible and relaxing the fascia plays a major role in the flexibility of the body which then allows and encourages muscle development and building.