Sleep Deprived

For the past three weeks, I've been getting fairly regular sleep and certainly have been getting at least the 7 hours I'm accustomed to. But for some reason, I still wake up and feel like I used to feel after getting just 5 hours of sleep. What gives?

Well, this morning, I read this article which might explain part of the reason for my constant exhaustion upon waking.

The other part might be the extra healing and recuping time I need after hitting the gym (which I've been trying to get back into).