title: Muscle crossbridge stroke and activity revealed by optical diffraction.
abstract: Optical diffraction measurements during rapid releases of active toad muscle show that the sarcomeres contract within 1 millisecond by an amount up to but not greater than 12 nanometers. This crossbridges immediately start cycling to produce the normal contraction velocity in unloaded muscle.
mesh_terms: D000818:Animals; D002024:Bufo marinus; D066298:In Vitro Techniques; D007700:Kinetics; D007834:Lasers; D009119:Muscle Contraction; D009132:Muscles / Q000648:ultrastructure*; D012542:Scattering, Radiation; D013710:Tendons / Q000502:physiology