title: Tension responses of frog skeletal muscle to ramp and step length changes.
abstract: Tension responses to ramp shortening of varying speed in whole muscle or single fibres from the plateau of an isometric tetanus, revealed at least two distinct phases. There was a fast initial drop in tension followed by a change of slope and a definite inflexion on the tension record. As the velocity of the imposed length change was increased, the inflexion point appeared at a lower tension. Similar inflexions were not observed during ramp releases to an elastic band or a segment of semitendinosus tendon. The tension records obtained with moderately fast ramp length changes to contracting muscle reflect the T1 and T2 phases of the tension transients.
mesh_terms: D000818:Animals; D004594:Electrophysiology; D066298:In Vitro Techniques; D007537:Isometric Contraction; D009119:Muscle Contraction; D009132:Muscles / Q000502:physiology*; D011894:Rana pipiens; D011896:Rana temporaria