I am a new lab owner. I am so confused about exercise and our puppy. Many books say don't run with dog until after a year but our breeder just said avoid the hard pavement as its hard on their joints. How much exercise should I be giving the puppy everyday? We like to do a lot of hiking and walking. What should I expect for puppy and this summer when he is 7 months old how much exercise at one time could I expect him to do?