Everything I've read about fitness and sleep during the past ten years has talked about the major importance sleep plays in rejuvenating our body -- lack of sleep can be as harmful as eating unhealthy foods! While I've been trying to change my schedule to wake up earlier, I often find myself waking up extremely tired. I justify going back to sleep because I tell myself it's probably healthier than waking up early. But then if I don't deal with lack of sleep for a few nights in a row, I'll never adjust my sleeping pattern.