When David Millar won the world time trial championship in the year 2003, I knew that he was doped. I could see that he didn't smile, he wasn't happy, everything about him told me that he was ashamed and disgusted. It took a little while, but suddenly he was involved in a doping story that ended with him confessing to having used doping and was banned for some years. Today he is a completely different person.
Since then, many years have passed, but the doped athlete's shame can still be seen in their faces and movements. Yesterday I saw a Russian athlete who had won Olympic gold medal in hurdles the day before and I could only shake my head and silently beg her, in front of the TV, "please, go and admit it.". She has doped, cheated, and I'm 101% sure about it. There is no way this woman had raced clean.
Believe it or not, athletes are human beings. They know when they've done wrong. And really,, it is difficult to lie. Even for mythomaniacs and other people who live. I have all the sympathy for athletes who take doping substances to improve performance, most likely I would have thought of it myself, but it's very seldom that doped athletes are proud of their decision to cheat. Almost everybody are ashamed. I'm pretty sure many of them would like to be caught and have a reason to stop, but for it's not that simple. When athletes get to a certain age or stage of life, at least that is my feeling, they decide to talk about it. They do no longer want to be ashamed of what they have done.
Today, the anti-doping controls work well, although they could be better, but hopefully the controls today and in the future, can help reduce the number of former athletes who walk around with secrets in the future.