So I am reading this book entitled Spinning Straw into Gold: What Fairy Tales Reveal About the Transformations in a Woman's Life and there is a section on sleep. Basically the book links the transformations of a woman's life and relates them to different fairy tales. In the section about sleeping beauty she talks a lot about how we as a culture avoid sleep because it isn't "doing something".
Here are some of the physiological thing that actually occur in your body when sleeping. In REM the inner organs wake up and start working at full steam. The blood flow to the brain increase by 40%, the heart speeds up and slows with no apparent reason, and your metabolism increases.
In deep sleep or slow wave, the lightest time of sleeping where no dreams occur, very important things happen. This is the time when links are forged in your brain. The short-term memory talks to the long-term memory and associations and connections are forged. In this period of sleep consolidation of significant memories is completed and the information is becomes available to you in a more accessible form.
So in fact hard work is NOT enough. *phew* I can stop running around like a chicken with it's head cut off in the attempt to do more. The author Joan Gould makes this great point that Sleeping Beauty goes to sleep a girl and wakes into a woman. Instead of suffering through the pain and agony of growing up she simply slept and let her mind and body sort things out. So on those days when life really is too hard to get out of bed for, maybe we shouldn't. Maybe it'd be ok to let ourselves dream our way out of the depression we are caught in.
Also when I say to my beginning students to sleep on the material and it will be easier in the morning there is some scientifically documented proof that this is true.