Skeletal muscle is striated muscle tissue that is attached to bones. It is composed of fibers that look like a mixture of dark and light bands bundled together that run along the bone. These muscles are responsible for contracting and relaxing when a person moves. Skeletal muscles are the muscles that we can see and feel through our skin.
An individual skeletal muscle is considered an organ within the muscular system of the body. The skeletal muscle works with nerve tissue, connective tissue and vascular or blood tissue. Skeletal muscles vary in different sizes and shapes as well as the arrangement of the muscle fibers. The sizes of different skeletal muscles range from as small as a muscle within the ear to a muscle large enough for the thigh. They may be broad or narrow, but no matter what the size, each skeletal muscle is composed of many muscle fibers that are wrapped and bundled together and covered by connective tissue.
The connective tissue covering is called the epimysium. The epimysium grows inward to divide the muscle into different compartments that contain bundled muscle fibers. Each bundle of muscle, called fasciculus, is surrounded by the perimysium. Each muscle cell within the fasciculus is protected by more connective tissue called endomysium.
Each skeletal muscle is attached to a bone on one end, stretching across a joint and is attached to the end of another bone. They are held onto the bone with tendons that work and move along with the skeletal muscle and bone when we move certain areas of our body. While skeletal muscle fibers are protected heavily within each layer, skeletal muscles are very fragile. These various connective tissues work to protect the skeletal muscle when it is contracting and provide a way for the blood to flow and nerves to work properly. An abundant supply of nerves and blood vessels provided within each skeletal muscle allow for proper movement.
The nervous system stimulates and controls skeletal muscle. A skeletal muscle will not move unless the nervous system tells it to. If nerves are damaged, this can limit movement throughout various parts of our bodies. For instance, if a person's spinal cord is damaged, his legs may be permanently paralyzed.
Lifting weights and working out strengthens the skeletal muscles and makes them stronger. Depending on variations of exercises, a person can make their muscles leaner or larger. Skeletal muscles work together with bones to give us power and strength.