28 October 2012 Last updated at 16:15

Cycling will never be fully clean - David Millar

Scottish cyclist David Millar tells BBC Scotland's Sport Nation that cycling will never be 100% clean but that there is now "an anti-doping culture" and "a level playing field" for people coming into the sport.

You can see more of this interview in Sport Nation's Cycling Special on BBC Two Scotland, Tuesday 30 October at 19:00 GMT