Lab Pup Exercise

Question
I have a 10 week old choc lab that walks once or twice a day (about 30 minutes each) with our 12.5 and 6.5 yr-old-labs.  She keeps up pretty good and is still finding her way within the pack.  She usually takes a good nap thereafter.  I don't feel like I'm pushing her at all on the walks, but want to make sure I'm not starting her out too early.  She doesn't come into close physical contact with other animals on the streets I take them so I'm not too worried about her not having all her puppy shots.  Can you verify that I'm doing the right thing...with the early walking and all?  Her future walks will be on the hiking trails in the California Sierras with us by summer's end.

Answer
It is noted over walking large breed puppies can cause joint problems I think 1 hour of straight walking a day for a ten week old is a bit much but others may say different...the bet thing to do would be to ask yuor vet about this issue as they would know best....I never walked my lab as a puppy she would pull like crazy and wasnt really walked until she was 8 months old when my vet reccomended a gentle leader head collar.