If you regularly wake up from seven or eight hours of sleep still feeling tired, your instinct might be to start aiming for nine or even 10 hours a night — but that move might not solve the problem.

I sleep eight hours a night but I'm still exhausted; what's going on? Sleep specialist Dr. Lindsey Browning explains my ...

If you feel more sluggish, sleepy, or unmotivated once winter sets in, you are not imagining it. The shorter days, cold weather, and lack of sunlight genuinely affect your energy. According to ...