I've been proud to be national champion.

I had grown used to getting a pat on the back and being told after a good result: 'Well done, David - you should be happy, you're the first clean rider.

But human nature dictates that there will always be cheaters. That's inevitable. Where there's money involved and glory, there are going to be people that cheat, and there will always be ways to cheat.

To be brutally honest, it's simple economics. If they want to come into cycling, sponsors need to know the team they are funding is clean, otherwise the risk is just too great.

People do make mistakes and I think they should be punished. But they should be forgiven and given the opportunity for a second chance. We are human beings.

I was awarded 'Most Aggressive Rider of the Day', generally given to the most spectacular loser of the day.

Often the best guys are just those that can suffer longer, who don't give up. And it's so easy to give up, when you're on a mountain and it's really hurting. We go through a lot physically.