Active state of muscle and the second and third derivatives of twitch tension.
D000818:Animals; D004558:Electric Stimulation; D005221:Fatigue; D066298:In Vitro Techniques; D051379:Mice; D009119:Muscle Contraction / Q000502:physiology*; D009132:Muscles / Q000502:physiology*; D009213:Myography; D013696:Temperature; D013997:Time Factors