I crossfit too. I use Crossfit Amarillo's site as my source for daily WODs as we don't have a crossfit gym in my town. The only thing that is killing me is tendenitis in my left arm and it really gets angry when we're doing pull ups (which is all the time) and it makes it sore when sailing in big wind usually holding the stick on my 17
Otherwise, I am not sore, tired or anything since I have been a disciple of the CF Wod. Best Crossfit total to date (at 46 years old and 192lbs: 880 (one back squat, dead lift and push press adding the weight together)