Key Concepts

• An alarming number of sports—baseball, football, track and field, and especially cycling—have been shaken by doping scandals in recent years.
• Among the many banned drugs in the cycling pharmacopoeia, the most effective is recombinant erythropoietin (r-EPO), an artificial hormone that stimulates the production of red blood cells, thereby delivering more oxygen to the muscles.
• Game theory highlights why it is rational for professional cyclists to dope: the drugs are extremely effective as well as difficult or impossible to detect; the payoffs for success are high; and as more riders use them, a “clean” rider may become so noncompetitive that he or she risks being cut from the team.
• The game theory analysis of cycling can readily be extended to other sports. The results show quantitatively how governing bodies and antidoping agencies can most effectively target efforts to clean up their sports.