Hello Sir/Madam, I'm A Boxer And I Have A Friend

Hello Sir/Madam, I'm a Boxer and I have a friend who is a professional Body Builder and he tends to be very stronger and has a much better physic. I asked what he does and what he eats. But he says its the work of steroids, and he does take them alot. I just don't get how he can pass through the medic test. And want to know if there is any other options other then taking steroids or other banned substance and get the almost the same result? Thank You