Schematics of sarcomere and M-band structure derived from electron microscopy of muscle [<b>1]</b>,[2<b> </b>].

<p>(a) Relaxed sarcomere. (b) After isometric contraction causing tension in the M-band and sliding between thick filaments; (c) M-band model showing M-bridges connecting thick filaments, as well as additional links connecting M-bridges.</p