I'm a huge proponent of regular exercise and, while I can ride distances and other stuff right now, I am mentally prepared for the day when that exercise is just a slow walk around the block. Never give up the exercise. On days when I don't feel like it, ..I force myself to get ready and go out the door --all the while rationalizing to myself that it's OK to just ride around the block and go back in. You don't have to DO the exercise but why not at least get ready and walk out the door --then decide.

The other thing I think is important is to make your exercise part of your lifestyle. If you want a coffee and donut from starbucks or dunkin every morning, ride your bike there to earn it. I ride to the train station every day for my commute downtown. It's short (2+ miles) but gets me SOME exercise.