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We investigated whether regular exercise exerts any significant roles in regulatory genes (i.e., fatty acid translocase [FAT/CD36] mRNA, carnitine palmitoyl transferase [CPT]-1 mRNA, β-hydroxyacyl CoA dehydrogenase [β-HAD] mRNA, pyruvate dehydrogenase kinase-4 [PDK4] mRNA, mitochondrial uncoupling protein-3 [UCP3] mRNA) and proteins (peroxisome proliferators-activated receptor [PPAR] α and γ ) expression, and enzyme (citrate synthase [CS] and [β-HAD]) activities that closely involved in lipid uptake and oxidation in skeletal muscle cells. Sixteen female Sprague-Dawley rats were used, and divided into two experimental conditions: either untrained (n=8) or trained (n=8). While rats in untrained group performed no training, animals in trained group undertook 8wk of regular exercise (4 timeswk-1, 1000msession-1) on the treadmill. The expression of all genes important for lipid oxidation tended to increase in trained group but statistical significance was only found in PDK4 (p<0.01) and UCP3 (p<0.05). Despite increases in the expression of some of genes involved in lipid metabolism, there was no effect of chronic exercise on PPARα and γ protein abundance in extensor digitorum longus (EDL) muscle (p>0.05). Similar to PPAR protein expressions, oxidative enzymes were not shown any significant effect following 8wk regular exercise program. This study suggested that activation of PPAR α and γ may not be necessary for the coordinated induction of fatty acid oxidative genes after chronically trained muscle. Additional studies examining the exercise duration and intensities of this molecular response, the major transcriptional regulators, and gene expressions should be undertaken.