The muscles of the body are connected by fascia. This is a thin film of fibrous material that allows muscles that are attached or crossed over each other to slide. Sometimes the muscles develop attachments due to injury or atrophy and “stick” to the fascia, stopping the natural movement from taking place. Sometimes, the muscles just don’t move much and get stuck together because there isn’t enough movement for them to articulate.
Muscles that don’t move may atrophy or because unable to respond. The nerves are not fed by vigorous circulation and the responses the muscles make may be “shut down”. This creates a situation where you can feel. Guess what, you can’t move what you don’t feel and you don’t feel what you can’t move. Dead end.
In order to get movement you must make the muscles move by some external means. If you have had a cast on your arm for a long time, the physical therapist will move your arm, stimulating the muscles and the brain, until the signals from the brain to the muscle and from the muscle to the brain take over and generate movement and sensation on their own, without outside help.
If the muscles involved in making voice sound (over 55 sets of muscles) don’t do more than conversational speech, they don’t move much. The excursion of the muscles isn’t very big (they don’t go far), and the movement are not refined, small and highly coordinated. The tongue (35 muscles) is very important because it is a large structure, right in the middle of the throat/mouth, and the larynx is suspended from it in the front. How do you move the muscles in the tongue, and separate them from each other, from other structures? What about the muscles in the back of the mouth? in the face? in the jaw and sides of the mouth inside? the neck?