Muscle fibers are arranged in bundles bound by dense connective tissue sheaths which helps to coordinate the force of contraction of individual fibers. A small population of satellite cells in adult skeletal muscle can divide and form new muscle after tissue damage. Skeletal muscle is responsible for voluntary movements of limbs, digits, and other structures. Skeletal muscle associated with the axial skeleton plays a role in maintaining posture. They exhibit a great deal of resistance to fatigue, and are suitable for maintaining sustained contraction.
Red fibers predominate in the muscles of the limbs.
They are also found in the intrinsic muscles of the back responsible for maintaining erect posture. While white fibers fatigue faster than red fibers, they are capable of generating large amounts of tension over a short period of time. This makes them ideally suited for rapid, precise, fine movements. White fibers predominate in the digits and extraocular muscles of the eyes. White fibers are more generously innervated than red fibers.