it's a really really inconvenient and sad truth that cycling is quite possibly the most steroid-ridden sport. everyone works so hard and gets paid so little, so when they receive the opportunity to near greatness, then most of them do end up taking that advantage
now, however, im fairly confident that with all the new technology and experience, pro cycling is nearly 100% clean. if you take something, they will bust you. the sport is heading in a great direction