Dolly, our 2 year old springer keeps both of us trim even though she eats far better people food then I do as a vegan. She lives to walk and hunt and so my day starts in the dark walking about every other hour and ends at dusk. Thanks to Dolly I am in better shape then most people half my age. If she ever starts to get heavy I will cut her food. She just came into the computer room for the next walk. This is the third walk this morning and it isn't light out yet.