In general, the main reason many players cheat with drugs is that doping is 'rational', based solely on the incentives and expected values of payoffs built into the competition. (Expected value is the value of a successful outcome multiplied by the probability of achieving that outcome.)

The concept of game theory - known as Nash equilibrium - identified by mathematician John Nash, who was portrayed in the film A Beautiful Mind, can be applied to discourage cheating in sports.

In essence, this means the doping game must be restructured so competing clean is in a Nash equilibrium - that is, the governing body of each sport must change the payoff values of the expected outcomes in the following ways:

When other players play by the rules, the payoff for doing likewise must be greater than that for cheating; and, more important

Even when other players cheat, the payoff for playing fair must be greater than that for cheating.

Players must not feel like suckers if they follow the rules.

In practical terms, this means higher cost of getting caught cheating (penalties and lost income), higher likelihood of getting caught cheating, and consequent new, lower likelihood that a non-doping player will lose out.

Game theory may well stamp out doping in sports such as cycling and athletics but with bodybuilding, where grotesque (some call it beautiful) muscles needed to win can be achieved only apparently by regular doping besides training, it may not work. Here, to discourage cheating, the application of the penalty 'one strike and you're out - forever' may be necessary.

Lee Seck Kay

HOW IT WORKS

In practical terms, this means higher cost of getting caught cheating (penalties and lost income), higher likelihood of getting caught cheating, and consequent new, lower likelihood that a non-doping player will lose out.