It's the dog's fault!

How do you tell your dog that you can't take him for a walk for various reasons, ranging all the way from too much pain all the way down to just too lazy. The dog expects to go for a walk every day now because a few weeks ago, he stayed with my daughter for a weekend and since she is much more disciplined than I am, he got a walk every day. All it takes to establish a habit with him is one time doing something he really enjoys. Now he wants a daily walk and doesn't often get it. Anybody out there up for the job of dog walker?
And speaking of habits: this dog is a cheese harlot! Any cheese in the vicinity gets his immediate attention. However, there is an upside to this: he is incredibly easy to train...just offer a bit of cheese and he will do whatever you ask.