Tour de France 2009

So how does an athlete systematically avoid being caught doping? Armstrong on tweeter stated that he had been spot tested eleven times during this tour - that is pretty much every other day - and aren't they checked in the off season as well?

Very simply, the testers are always a step or two behind the dopers. There was no test for EPO until the 2000 Olympics, so usage was rampant throughout the 1990s. There is still no reliable test for autologous blood doping, i.e. the removal of your own blood to be reinfused later, increasing your red blood cell count.

A lot of the big names caught in the last few years have been caught because of criminal investigations (Puerto, Freiburg, the Oil for Drugs scandal in Italy) yet all these riders (Basso, Ullrich, Kloeden, Di Luca) have continued to pass the tests until they get nailed by the criminal justice system. The pendulum seems to have swung back towards the testers, i.e. Ricco, Schumacher, Kohl and Di Luca all getting busted for CERA, but even then some riders seem to have escaped detection, i.e. Di Luca knew they could detect CERA yet still used it, presumably because he'd been advised that it was possible to use it undetected.

The biological passport should improve the situation, but they need a baseline to work from and that takes a year or so to build for each athlete. It would also appear that an athlete can, if they are so inclined, dope at a consistent level that can be undetected by the biological passport. We'll see how it works out, but I don't doubt for one minute that a) riders have been doping in this Tour and b) some of them will be caught for it at a later date.