The notion that Olympic medal winners are increasingly youthful does not bear scrutiny.
At the 1976 Olympics in Montreal, teenagers and the 30-and-older crowd earned 10 medals each in track and field. Four years ago, in Sydney, Australia, the oldsters beat the teenagers in a rout in the track and field events, 46 medals to 4.
The shift has helped to alter athletes' and scientists' understanding of when the human body peaks. For years, people assumed that the early- and mid-20's marked the last time athletes could run their fastest or jump their highest. It was a sensible assumption, because that was the age of the world's champions.
Economic forces lurk behind this change. People often decry the influence of money in sport, yet with it comes the ability to earn a living from athletics. This enables the world's best athletes to remain in training, which has an impact.
[I]t now looks as if the reason was more economic than biological. Before the Olympics allowed professionals to compete, athletes had to retire, or curtail their training, and find jobs before they turned 30. They were quickly replaced in the winner's circle by younger athletes practicing full time.
One implication of this is that the effects of inactivity can be mistakenly attributed to aging. As Lance Armstrong would say, get off your duff and get on the bike. You'll age better.