Fig. 6. Mitochondrial and glycolytic enzyme activities at 3 °C for frog skeletal muscle at different stages during hypoxic hibernation. Mitochondrial enzymes: citrate synthase (CS), cytochrome c oxidase (CCO) and NADH dehydrogenase (NDH). Glycolytic enzyme: lactate dehydrogenase (LDH). Values are means + S.E.M.; N=6 for control frogs, N=4 for 1-month-submerged frogs and N=5 for 4-month-submerged frogs. Statistically significant differences (P<0.05) between groups of frogs are represented by different letters (one-way ANOVA and a posteriori Tukey test). From St-Pierre and Boutilier (2001) with permission.