The kinetics of cross-bridge attachment and detachment studied by high frequency stiffness measurements.
Muscle fiber stiffness, supposedly an indication of attached cross-bridges, was measured throughout tetanic contraction and subsequent relaxation. Stiffness increased at a rate faster than the development of force during the rise of tetanic contraction and decreased more slowly than force during relaxation. One explanation for these results is that long-lived cross-bridge states may exist between attachment, force generation and detachment.
D000818:Animals; D066298:In Vitro Techniques; D007700:Kinetics; D009119:Muscle Contraction; D009126:Muscle Relaxation; D009132:Muscles / Q000502:physiology; D009210:Myofibrils / Q000502:physiology*; D011896:Rana temporaria; D012518:Sarcomeres / Q000502:physiology*; D013314:Stress, Mechanical