Re: Proper Exercise for puppies
This is going to be an interesting topic. I try to break this into a couple of different topics that have highly varying opinions:
Stress management-i.e. things like the stair issue. what can you do in terms and relation to the development of a dog's growth plates and maturing of their bone structures. For smaller dog breeds the closing of the plates occur much sooner than the gsd or larger breeds. So the gsd/large breed owners need to manage stress induced exercises for a much longer period.
Vaccinations schedules - when during the early vaccination period can you get the puppies out and about and what you need to continue to protect them from. This can go from the (IMO) extreme of "I have to keep my puppy isolated and protected from everything until after they complete their vaccinations and get their rabies shots" to getting out and socializing after the first/second round of shotts. The timing of getting rabies also varies from around four months to six months these days.
My puppy - I allowed to climb stairs from the day he came home but I carried him down the staris to avoid stress on his joints for the first few weeks. And then he went down with a leash for a while to keep him from racing down and launching off the stairs. Next phase was placing obstacles at the bottom to keep him from launching off the bottom of the stairs. He was in a puppy class at about 11 weeks and going to a local park to run and socialize with dogs of owners who I knew but I kept him away from certain owners or dogs who I hadn't known previously. Also kept him in the center of the parks and away from the bushes from areas where the animals were likely to defecate more. He was at the regional parks and hiking/swimming in the lake at 3.5 months.