The effect of tension in prolonging the active state in a twitch

Abstract

During an isometric twitch the heat production continues as long as the tension does. But if the tension, when near its peak, is suddenly reduced to zero by a short quick release the heat production stops. The energy liberated is then 15 to 20% less than in the isometric contraction. It seems as though a kind of weak positive feed-back occurs, tension prolonging activity and activity prolonging tension with the liberation of extra energy.