The dirty little secret in sport used to be money. Champions were turned into criminals, forced to queue up for illegal cash payments handed out in brown envelopes. Why? Because top-level sport was a full-time profession - you could not hope to achieve world class by training after hours - but sports champions were supposed to be amateurs. Today, sport's dirty little secret is drugs, and it is high time we made them legal. Performance-enhancing drugs may not be desirable, but they are here to stay. What we can do away with is the hypocrisy.
Insiders know that many - perhaps most - top players in all sports take drugs to train harder and feel no pain during play. The trainers, sports doctors, nutritionists, physiotherapists and managers of the big names make sure banned substances are taken at the safest and most efficient levels, and when they can, the governing bodies look the other way.
The fastest man on the planet and the world's top endurance athlete have just failed drugs tests. The runner Justin Gatlin, the current Olympic 100 metres champion and co-holder of the world record, and the cyclist Floyd Landis, winner of this year's Tour de France, are getting some bad publicity, but they are in very good company. Cricket, football, tennis and speed skating have all had scandals involving anabolic steroids, growth hormones, blood doping, diuretics, amphetamines, or, like Gatlin and Landis, testosterone boosts. You name it, someone takes it if it will help.
What many of us don't realise is that sports doping rarely gives you a free ride. If you or I were to take anabolic steroids and sit down in front of the telly, we would not build muscle or speed or endurance. Drugs allow you to train harder. They help you recover more quickly from a hard session so you can work hard again the next day. Some drugs boost the body's propensity for building muscle or its ability to use oxygen, but you still have to do the work. A judo medallist once told me: "I took drugs so I could train twice a day. I don't feel any guilt because I know I earned my medal."
This season, the British 100 metres runner Dwain Chambers, who was stripped of his 2002 European Championship title, is back on the team after a two-year ban for taking a designer steroid. The man who welcomed him back, the performance director of UK Athletics, Dave Collins, said: "We are not making ethical statements. We are picking a team to do as well as we can."
Tales of sport doping go back to ancient Egypt, where the hoof of an Abyssinian ass ground up and boiled in oil was prescribed to improve performance. In the 19th century, boxers took heroin before going into the ring. The legendary 1960s Manchester United goalkeeper Harry Gregg has confessed that he took amphetamines before matches.
No one much cared until 1960, when a Danish cyclist on speed died during an Olympic competition. None the less, it was seven years before the Olympic authorities issued a banned-drug list. Anabolic steroids were not prohibited until 1976. Champions and the testers have been playing cat and mouse ever since.
The main effect of banning such substances has been to turn performers and their coaches into liars and cheats. We should legalise performance-enhancing drugs so that they can be regulated and athletes on the way up - whose entourages do not yet include savvy physiotherapists and doctors - don't overdose and do themselves damage.
Hunter Davies is away