Muscle Force Depends on the Structure of Muscle• The proteins are arranged in repeating sets of thick and thin filaments, each set known as a sarcomere• The physiological length of a sarcomere, which is bounded by Z disks, ranges from 1.5 µm to 3.5 µ m.• The force that each sarcomere can generate arises from the interaction of the contractile thick and thin• filaments.• To maximize the interaction between the globular heads and the thin filaments, six thin filaments surround each thick filament.• The Sarcomere Contains the Contractile Proteins: Myosin & Actin• Sarcomeres _myofibril_ muscle fiber.