In Experiment 1a, rats trained to escape shock by performing a 2-s inactive response were less impaired on a subsequent 2-way shuttle response than their yoked counterparts that received inescapable shock. In contrast, in Experiment 1b, rats trained to escape shock by performing a longer duration inactive response were more impaired on the subsequent escape task than their inescapably shocked counterparts. In Experiment 2, the results of Experiments 1a and 1b were replicated, and the inactive responses performed during pretreatment by both the escapable and inescapable shock groups were assessed and correlated with test stage 2-way shuttle escape performance. These activity data indicate that inactivity during pretreatment shock in both escapable and inescapable shock groups was a highly reliable predictor of subsequent 2-way shuttle performance, irrespective of the pretreatment shock contingency to which these Ss were exposed.