Genes and response to aerobic training

Prolonged endurance training elicits a variety of metabolic and morphological changes, including mitochondrial biogenesis, fast-to-slow fiber-type transformation, and substrate metabolism. Endurance adaptation results in increased muscle glycogen stores and glycogen sparing at submaximal lactate kinetics and morphological alterations, including greater type I fiber proportions per muscle area, and increased capillary and mitochondrial density. Repeated bouts of endurance exercise result in altered expression of a multiplicity of gene products, resulting in an altered muscle phenotype with improved resistance to fatigue. The effects from aerobic exercise differ greatly among individuals, depending on lifestyle factors and genetic backgrounds. The heritability estimate of the VO2max response to training was reported to be 47%. In this chapter, we consider molecular mechanisms involved in skeletal muscle changes after endurance exercises, starting from DNA polymorphisms, evaluating epigenetic transformations, discussing the regulation of key genes regulating oxidative metabolism, and integrating them in gene networks involved in the regulation of aerobic muscle performances. We also consider the involvement of noncoding RNAs in the response to the aerobic training. At the end of the chapter, we also considered beneficial effects of aerobic exercise on human health.