I get that, and when i crouch etc i can hear little noises etc (my friend who does a lot of running gets the same thing, I've asked about it, and was told that it's the cartillage), mainly muscle pains though, but they all stoped after the 1st month or so of riding. I don't think trials is that bad for breaking people though, other sports are much worse, you ever seen some of the bails in downhill? But there are good points to what it does to your body...