A New England Journal of Medicine article explores the history of the Olympic Games as an object of "medical scrutiny," with some interesting highlights:
Physicians have been interested in the Olympics for many reasons. In the 1920s, they probed the limits of human physiology. One group studied the Yale heavyweight rowers who won gold in Paris. An ingenious contraption revealed that at their racing speed — 12 mph — the eight men produced four horsepower, a 20-fold increase over resting metabolism (1925). A 1937 study published in the Journal showed that athletes at the 1936 Berlin games consumed 7300 calories each day (1937).
Of course, physicians are currently most fascinated by the effects and progress of performance-enhancing drugs: