<prompt> Resting muscle length means?Length of actin and myosin before contractionThe length of the muscle fiber at the onset of contraction which is required to attain maximum active tensionIt is about 4 micrometersLength at which muscle has minimal tension  <response>: Resting length: The length of the muscle fiber at the onset of contraction which is required to attain maximum active tension It is about 2 micrometers. Also known as optimum length. At this state, the ends of actin filaments extending from 2 successive Z disks barely overlap one another. 