This week may well go down as the most tumultuous in the history of professional cycling. Indeed, it will be a moment to remember for the entire sports world.

It is clear now that Lance Armstrong is the biggest cheat professional sports has ever seen, according to the United States Anti-Doping Agency. The International Cycling Union, cycling's governing body, agrees.

In many ways, Armstrong's troubles have only just begun, with many demanding repayment of ill-gotten gains and threats of lawsuits coming fast and furious.

Cycling's troubles are, of course, far from over.

The biggest bike race in the world — the Tour de France — now has no official winner from 1999 to 2005. Imagine the NHL, MLB or NFL declaring no winner for seven years despite all games being played as usual.

And yet the attempt to rehabilitate cycling began Wednesday in Paris as Tour de France organizers unveiled the route for next year's race. But even before he announced that, Tour de France director Christian Prudhomme said no one was doing more about doping than his organization.

He said that even before the Armstrong revelations, the Tour had cancelled the victories of two other "winners" in recent years for doping.

"The Tour de France is our cultural heritage," Prudhomme said. "It is stronger than doping."

The issue may now spread to the entire sports world, much as it did when sprinter Ben Johnson tested positive at the 1988 Seoul Olympics.

Mark Cavendish, cycling's world champion in 2011 and currently one of the top riders, figures there are cheats in every single sport.

"If you put the time, the effort and the money into catching them and you have the structure that does it properly, you're going to catch a cheat," he told the BBC. "This is why cheats get threaded out of cycling now.

"It doesn't happen in other sports. Not because other sports are clean, but because it's not got the structure that cycling's got to do it, so it's not fair to tarnish cycling as a sport that's dirty.

"In my eyes, it's the cleanest sport. It's doing everything to combat this."

The penalties for doping tell part of the story. A first-time offender in cycling gets an automatic two-year ban. A first-time cheater in professional baseball gets 10 days. In the NHL, it's 20 games for a first offence.

Another part of the story is how rigorous the testing program is, something Cavendish was alluding to. Cyclists are subjected to out-of-competition tests year-round. They can be ordered to pee in a cup by a tester during an unnanounced visit to their home at any time.

Biological passports

Cyclists also have "biological passports," meaning their blood is sampled regularly and the results are examined to look for abnormalities which would suggest they are getting blood transfusions.

Compare that to the NHL. Players can only be tested during the regular season and cannot be tested more than three times a year. Many aren't tested at all — and never in the off-season. Some say the only time any of them are at real risk of testing positive is when the Olympics roll around.

In his book published last year, former NHL tough guy Georges Laraque wrote, "You just have to notice how some talented players will experience an efficiency loss as well as a weight loss every four years, those years being the ones the Winter Olympics are held. In the following season, they make a strong comeback; they manage a mysterious return to form."

Laraque said the scourge of steroids has been commonplace in the NHL for years. But just a few months ago, Matthieu Schneider of the NHL Players' Association said performance enhancing drugs are "not an issue in our sport."

This, despite the revelations that came out in the case of Derek Boogard. Following his death in 2011, the medical examiner concluded Boogard died of an accidental overdose of alcohol and oxycodone. It was subsequently discovered that Boogard and other players used oxycodone — a powerful and addictive painkiller — for years.

Oxycodone is on the prohibited list of the World Anti-Doping Agency. In other words, anyone caught taking it during the Olympics would be kicked out and labelled a drug cheat.

Code of silence

For a long time, cycling was dominated by a phenomenon known as omertà — the code of silence.

Even though virtually everyone in the sport knew what was going on, talking about it was forbidden. The few who did talk were ostracised, ridiculed, threatened and chased out of the sport, sometimes by Lance Armstrong himself.

The only reason we now know the full truth about cycling is because, in the past two years, the omertà broke down. Those who knew started to talk. Now we have the USADA report and its sworn affidavits as well as tell-all books by cyclists who doped, including David Millar and Tyler Hamilton.

Clearly, omertà still exists in the NHL and in many other professional sports as well.

Will this latest doping scandal crack it?