Muscles are constructed of bundles of fibers contained within protective sheaths called fascia, which are then themselves bundled together. The biggest bundle is the muscle itself. Next in line are the fascicles, which contain the long, single-celled muscle fibers. Muscle fibers are then sub-divided into myofibrils, which are divided again into bundles of myofilaments, made up from chains of sarcomeres.
1. Tendon - strong tissue that connects muscle to bone.
2. Epimysium - A layer of connective tissue that encases the entire muscle.
3. Endomysium - Connective tissue that covers the muscle fibers and also contains capillaries and nerves.
4. Perimysium - A layer of connective tissue that bundles together between ten and several hundred individual muscle fibers into fascicles.
5. Fascicle - A bundle of individual muscle fibers.
6. Myofilaments - The smallest fiber bundles in your muscles.
7. Muscle Fiber - There are two main types of muscle fiber: type 1 or slow-twitch, which are slow to fatigue and best suited to endurance; and type 2 or fast-twitch, which fatigue quickly and are suited to fast, explosive movements.
8. Blood Vessel - Blood vessels come in three types: arteries, which transport oxygenated blood away from the heart; veins, which transport de-oxygenated blood back to the heart; and capillaries, which enable the exchanges of nutrients and waste products between the blood and tissues.