But future technology will render such details ever less restrictive. Runners lacking those genes can compensate by training in ways that optimize what they have. The protein products of those genes might be supplied as drugs. Whether those techniques would be safe is another story, however, and future Olympic committees might look as dimly on them as they now do on blood doping and steroids. The most vital training always goes on between the ears.
Great athletes muster the courage to push their bodies to the limit, over and over again.
And in the crisis of competition, their determination holds them up, telling them with every heartbeat that they must win because they will not lose.