I meant to respond to this thread a few days ago (in fact, I thought I had... hmmm... where'd my post go???)

Anyways...
Just wanted to add that remember to have a nap or rest after a good workout is a natural part of your body's recovery from the the demands you have placed on it.

After a solid or long ride, you should typically want to eat something, and then want to shut your eyes or just blob for half an hour or so.
Very natural and very important in the development of your fitness.

Effective recovery is as important as the workouts themselves.