Exercise combined with resveratrol supplementation upregulated mitochondrial oxidative enzymes but did not promote myofiber specification toward slow-twitch type. The activity of ATPase (A) and CS (B) were examined by microplate method. Cty C content (C) was determined by ELISA. Western blot and quantitative analyses for CPT-1M and PDK4 were normalized by β-actin (D). MyHC isoforms with mRNA normalized against β-actin in the fast-twitch extensor digitorum longus (EDL) (E) and slow-twitch soleus (SOL) (F) muscles were detected after the four-week body weight loss programs: control (Cont), exercise (Ex), resveratrol supplementation (Res), and exercise combined with resveratrol supplementation (Ex + Res). The bars represent mean ± SEM (n = 6). P values were calculated by one-way ANOVA. *P < 0.05, and **P < 0.01 vs. Cont mice; #P < 0.05 vs. Ex mice; &&P < 0.01 vs. Res mice.