Retrospective analyses in the general population habits show that regular exercise is a protection factor for the metabolic syndrome and type 2 diabetes, among many other diseases. Randomized controlled studies in at-risk population have investigated the impact of lifestyle programs, including diet and physical training, on the incidence of diabetes, confirming physical exercise as a cornerstone in the strategy of the prevention and treatment of type 2 diabetes. Although public health recommendations regarding regular physical activity are available, however often little is done by governments to implement them. Finally, the general practitioner is pivotal in counseling patients regarding their lifestyle and therefore in affecting a large number of people.