Runner introduction: Every skeletal muscle in the human body is composed of muscular part and tendon part. The muscular part is called the muscle belly, which is composed of muscle fibers and has the ability to contract and relax. The tendinous part is called tendon, which is mainly composed of collagen fibers. It is white, tough and has no contractility. Muscles are attached to bones by tendons. Muscles come in many shapes and sizes, from large lamellae in the back to tiny strips in the hands. The shape and size of a muscle determines its contraction force and special functions.
Attraction