Figure 1. The figure illustrates the interpolated twitch technique (ITT) which was used with a maximal voluntary contraction (MVC) to estimate the extent of inactivation during a voluntary contraction by comparing the amplitudes of evoked doublets superimposed upon a MVC, with the post-contraction potentiated doublet (interpolated doublet amplitude / potentiated doublet amplitude x 100 = percentage of muscle inactivation).