PED's are rife in sport especially athletics; its a game of cat and mouse and governing bodies are a long way behind. They test for known substances and freeze 'B samples' for future testing because they are fully aware of current athletes cycling substances that are unknown. We're not just talking your generic anabolic oils, its hormone releasing peptides, EPO, gene cycling...the list is endless depending on how you desire to manipulate the body and its DNA.
Dopers are always ahead and anything/everything is available on the black market beit at the local gym or via the internet. It's not just the Russian's and Seb has no chance in guaranteeing a clean 2016 in Rio.