Lance actually admitted to Men’s Journal that his sex drive kinda blows.  He says,

I had sex if I had the energy.  I wasn’t one of those guys who believed in the myths about the guy losing his chi.  The fact is that if you are riding your bike six, seven hours a day, you are not a sex champion.  You’re just not.  You have fatigue, low testosterone and a lower libido.  But you know, I never got any complaints.

He threw in that last line after he realized he couldn’t take back what he had just said.  That truth serum’s a bitch.