Smooth muscles are found in the hollow parts of the body. This would be in places like the stomach, intestines, blood vessels and the bladder. Smooth muscles are arranged in layers with the fibers in each layer running in a different direction. This makes the muscle contract in all directions.

A smooth muscle is an involuntary muscle. This means that you cannot consciously control this muscle. These muscles are under the control of autonomic nervous system. This system controls many systems without us being aware of them.

Your strongest muscles are the masseters on each side of your mouth. They allow you to bite into things with a force of 73kg (160lb).