Factors relating to the environment and lifestyle central to the development of type 2 diabetes. In recent decades, research has focused on a variety of approaches – pharmacological, dietary and physical activity – to preventing and treating this disease, with generally encouraging results. With lower cost and fewer side effects, lifestyle modifications have been proven to be as effective as drug therapies, cutting by half the risk of diabetes in people who are at high risk. These results unmistakably indicate that people can stay healthier for a longer period of time, delaying or even preventing the onset of type 2 diabetes, by being physically active and eating well. In some studies, exercise alone or exercise plus diet can produce better effects than an intervention based on diet alone, which confers on exercise a vital role in the prevention of diabetes. Here, César Oliveira makes the case for prescribing physical exercise to combat type 2 diabetes.