Invited Commentary: Is Strenuous Activity Good for You? The Legacy of Ralph Paffenbarger.

Ralph Paffenbarger, Jr, MD, DrPH (1922-2007), was initially trained as an infectious disease epidemiologist at the Johns Hopkins School of Hygiene and Public Health (now the Bloomberg School of Public Health). He was the first Epidemiology Intelligence Service officer in the first Epidemiology Intelligence Service class. He joined the National Heart Institute (now the National Heart, Lung, and Blood Institute) in its very early days and later became a faculty member at Stanford University and Harvard University. His studies of the relationships between physical activity (PA) and coronary heart disease in longshoremen and in college athletes at Harvard University and University of Pennsylvania, as well as the follow-up of the Harvard College students to evaluate PA both in and after college that was detailed in the article "Physical Activity as an Index of Heart Attack Risk in College Alumni" (Am J Epidemiol. 1978;108(3):161-175), established that more strenuous PA reduced the risk of heart attack and that it was necessary to continue PA after college. Results from his studies suggested that less strenuous PA had little effect on risk of heart attacks. He was a strong advocate for the importance of PA in the prevention of heart attacks and as a public health recommendation and for the idea that adherence to strenuous PA over the course of a lifetime was difficult. He was a marathon runner who competed frequently in the Boston Marathon and practiced what he preached.