Over the last 50 years, Bengt Saltin's contributions to our understanding of physiology of the circulation, the matching of the circulation to muscle metabolism, and the underlying mechanisms that set the limits for exercise performance were enormous. His research addressed the key questions in the field using sophisticated experimental methods including field expeditions. From the Dallas Bedrest Study to the 1-leg knee model to the physiology of lifelong training, his prodigious body of work was foundational in the field of exercise physiology and his leadership propelled integrative human physiology into the mainstream of biological sciences.