Fig. 4. Percent decrease in plasma lactate per hour in trained and untrained turtles swum from 0 to 2 h during recovery from anoxic submergence. Each point is the % decrease in plasma lactate from the preceding time point divided by the time between the samples. Values are mean ± S.E.M. (N=6–9). Differing letters indicate significant differences between time points within a treatment. Differing numbers indicate significant differences between treatments at a specific time point (two-way RM-MANOVA, Student's t-tests, P<0.05). PR, passive recovery; AR, active recovery; U, untrained; T, trained.