MUSCLES AND MUSCLE TISSUE. Muscle is composed of fibers, nerves and connective tissues and account for over 40% of the body weight. The fibers contract to produce tension on the associated tissues or tendons.Muscle tissue is enclosed in facia, which in turn is attached to other structures including ligament.There are three types of muscle tissues: skeletal, cardiac and smooth muscles. Muscle tissue provides a) posture and body support b) locomotion and c) heat production.. FUNCTION AND TYPES OF MUSCLE. Locomotion: One of the most obvious functions of muscle tissue is locomotion. When muscles contract, the fibers pull or relax bones to which they are attached, thus causing locomotion.