OBJECTIVE: To evaluate the effect of aerobic exercise on genome expression in human skeletal muscle. METHODS: Six healthy sedentary elderly men aged (66+9) years were selected from military cadre retirement centers and after exercise. Testing indices included height, weight, vital capacity, step index and maximal oxygen uptake. Needle biopsies were obtained from the skeletal muscle before and after the last training. Total RNA extracted from the samples was hybridized to Affymetrix U 133A platform, the gene expression datum was analyzed.RESULTS: Aerobic exercise was shown to improve cardiorespiratory function and reduce body fat of elder subjects. It could alter the genome expression in human skeletal muscle, the number of genes that passed filtering criteria was 725. The most differently expressed genes (n=20) were investigated in this study, in which there were 3 upregulated and 17 downregulated. According to gene function annotations, the differential genes were classified into 8 categories which concerned cellular component and biological process, Kyoto Encyclopedia of Genes and Genomes (KEGG) searching showed 4 genes' metabolism pathway. CONCLUSION: Systematic aerobic exercise upregulates expression of enzyme genes concerning tricarboxylic acid cycle, and downregulates expression of genes conceming muscle protein synthesis and sphingolipid. It is suggested that aerobic exercise is good to protect human nerves' integrity, exerts positive action on anti-aging and accelerate the aerobic metabolism of lipid materials in vivo.