I walk. Fortunately (!?

) I live at the top of a long hill and walk down to get the newspaper - and then get back up as fast as my metabolism allows.
The other thing I do in my study at home is to work out with two 11 pound barbells. The beauty of this type of workout is that it is private, you can do it when you want and you can easily adjust the regime to suite yourself if you are not feeling energetic for one day. I am keeping muscle tone and development but anyone that doesn't want that can just use lighter weights for plain exercise.