2-3 miles 5 days a week. Approx 1 hour a day.
If it's a REALLY hot and humid day, he will get tired faster. But in general, he can go for a while. He is 2.5yrs old but has been walking a lot since he was about 6 months.
It's funny... he is 16lbs and his little Yorkie girlfriend Nala is only 6lbs and he got tired before her on our 2.5 mile walk at the SPCA walk for the animals, lol. That little girl can go and go and go. She walks 4-5 miles a few times a week.
Being tuckered out is a GOOD thing
That's why I love taking him on long walks. Sunday he did about 3 miles of walking and then 2 hours at the dog park and then another 3 hours at my dads house running around the backyard. Yep, he was pooped!
Training... have you looked into the no pull harnesses? Premier makes them and I think Walmart sells some varieties of them.