This article summarizes the scientifically validated evidence regarding the health benefits of physical activity, particularly in preventing the development of chronic diseases. At least thirty minutes of moderate physical activity per day is associated with a 30% reduction in mortality. This type of beneficial effect is observed even among sedentary individuals who begin engaging in at least moderate physical activity during adulthood. In the author’s view, it is more important than ever to promote physical activity “on a daily basis and throughout life.”