I've found one of the best ways to exercise my Gordons, as well as the grandkids when they come, is to put them together. Get a big pack of tennis balls and give them to the kids to play fetch. Make it a game so it'll be fun for the kids as well as your Gordon. Give them a little timer to time the Gordon's fetch. It'll be loads of fun and believe me, it'll run off that extra energy in your kids as well as your Gordons.