Remember also that a bunch of athletes potentially bound for Beijing were caught before the games. Athletes who are caught by in-competition testing anymore are either reckless or dumb. They are likely using outdated PEDs and using them in quantities large enough and timed close enough to competition that they will likely get caught. There are newer PEDs that are not being tested for (and there was still no adequate test for HGH for Beijing) and athletes can use them during 9+ months of training build-up and cycle the PED protocols to a lower level (like taking medication at a lower dosage/interval) and then completely off of them with a safe amount of time to spare to show up clean, both for the in-competition testing and for the stored samples that could be subjected to newer tests at a later date. The athletes (often via agents or coaches) will have their own testing facilities available to help them work out the protocol/cycle to ensure that they will show up technically clean for competitions, yet with the advantages of having done all their training with PED help. WADA and USADA make it tougher for athletes to dope via out-of-competition testing, yet WADA can only reach so far and USADA only pertains to US athletes and competitions. So, there are plenty of foreign runners whose national federations have no real out-of-competition testing or they hide out in training locales far from their 'homes' to make it difficult (if not impossible) for their cash-strapped national federations to send out-of-competition anti-doping agents after them.