My labrador-pit bull has a new preocupation. She spends hours standing in her new wading pond. Its about 8 feet in diameter and only 4 inches deep but its enough to activate her water dog instinks. She now gets plenty of exercise playing in the pond, and running in a new 1/2 acre fenced dog yard (with 8 foot fence to keep deer out).
I got a 3 wheeled kiddy stroller for jogging and stripped it down. I'm making a dog sulky so my dog can pull me up and downthe street, that should keep her nails worn smooth.
Its fun to see the lab/bird instincts - the bigger the splash the quicker she grabs them. She pauses just a split second when she approaches, then her head darts out and grabs it with an incredibly gentle mouth.
These are my own opinions based on wisdom earned through many wrong decisions. Your mileage may vary.