My vet thinks the obedience will be good for them and thankfully I never planned to compete with my boys! She said that we must just watch for justifiable reluctance to do an excercise and if we wanted, we could give them anti-inflammatories before exercise. I think I'd rather know when what they're doing is hurting and stop doing it!

Thanks for the advice, I'm just overly cautious about Digby, not sure how to stop a raging lunatic from running and jumping!!