Just remember that he still needs his exercise!! I'd stick to short walks, and lots of play time inside. My lab/boxer mix chased a laser light like crazy, so since it's cold here we just have her chase the laser light in the house back and forth til she's worked up a good thirst. It also works at night when it's dark out and you can see the light really well, we let her chase it around the backyard a good ten laps or so to wear her out before bed.