In this episode, we talk with Prof. Claude Bouchard, who is a Chair in Genetics and Nutrition at Louisiana State University. His research focuses on the genetics of obesity and co-morbidities as well as on the genetics of cardiorespiratory fitness and adaptation to exercise. We speak with him about how our genetic makeup can affect the individual variability in the response to different types of exercise. We discuss the evidence that our genes can affect our response to exercise, especially in relation to cardiorespiratory fitness. We then talk about which specific groups of genes could drive the effect and to what extent exercise can change the behavior of our genes through epigenetic modifications. We also talk about using genetic information in the context of precision medicine and in the identification of athletic talent. A wonderful conversation with one of the best exercise geneticists in the world.