So I went to a training class and found out with large breed puppies you gotta be a lot more careful about their exercise.
From the time I got my puppy at 7 weeks old I was walking/jogging her around the block. When she would lay down after a little bit I would let her take a break, though honestly since she was always laying down any time I took her outside to play I thought she was just being stubborn.
I took her jogging one night and noticed that the whole time she lagged behind me, with a bit of tension on the leash for most of the jog. I probably went a mile that night and in retrospect, knowing what I know now, I feel bad.
I also started her on stairs from day one that I had her, and within a few days she was handling them on her own just fine.
She's a day shy of 10 weeks and since Sunday (when I found out to be really careful about their exercise) I have taken it a lot easier on her. Just short walks around the block a few times.
A lot of the walking/jogging was on pavement.
Without this exercise she would be too much to handle. I don't know how else we'd get her enough exercise without at least the walks.
Should I be worried?
Making her use her brain is much more effective at making her tired than making her use her body. First of all, you shouldn't "exercise" a puppy that age at all - off leash runs are fine as long as you monitor her body language - i.e. don't force her to continue when she sits/lies down etc.
As for making her tired, until she's 16 weeks, socialization will take a lot of her energy. Bring her to all sorts of places and just hang around and let her take in the surroundings. Fields, the city, parks, crowded areas, trains, busses, the subway, introduce her to lots of people and other animals (horses, cats, cows, whatever) - but don't push her, always allow her to take in the impressions in HER pace and make sure she only gets positive experiences with places, peoples and animals.
After the socialization-phase, you can do all sorts of exercises to tire her. Off-leash walks is good - use the time to train recall and contact exercises. Make her use her nose and start doing some tracking foundation work. Make her use her brain with puzzle toys and feeding her in the yard (spread some kibble in your backyard and let her search for it).
All this info is also available on these forums - just do a search on the term "puppy energy" or something like that :-)
Good lucky with your puppy and don't be too hard on her :-)