Just Plain Sleepy
Feels like...your brain's in a fog and it's nearly impossible to keep your eyelids at full mast.
The Cause: You're generally getting less than seven hours of sleep. While everyone requires a different amount, most people need seven to nine hours to feel fully awake, according to the National Sleep Foundation. "When you deprive yourself of rest—particularly after 9 P.M., when the sleep-inducing hormone melatonin is naturally released—your body switches to a slower survival mode," explains Michael Breus, PhD, a fellow of the American Academy of Sleep Medicine. "Your metabolism slows down to conserve energy, and your alertness takes a nosedive."
The Cure: Reset your sleep clock. It's not enough to get more sleep on the nights you're exhausted, says Breus. Going to bed and waking at the same time every day is the best way to get your sleep cycle to match up with your natural circadian rhythm. This will regulate melatonin production and train your brain to be alert when you need it to be, so you'll feel less groggy during the day.
Feels like...an overall sense of weariness that's distinct from sleepiness but still leaves you wiped out.
The Cause: Stress. When the stress hormone cortisol is released, it interferes with the functioning of relaxing neurotransmitters like serotonin. As a result, you're left dragging. "When you're chronically anxious, you're stuck in a low-level 'fight or flight' mode that will eventually exhaust your entire body, from your brain to your muscles—which are often knotted from tension," says David Katz, MD, director of the Yale University Prevention Research Center.
The Cure: Resist the urge to crawl under the covers; instead, do something fun to counteract your anxiety, says Katz. When you call a friend, go for a walk, or engage in any other activity you enjoy, you divert your mental focus, which can reverse the influx of stress hormones. Your cortisol level should normalize, and you'll slowly begin to feel refreshed. And when you do finally get into bed, your serotonin levels will have been restored, and you'll sleep more soundly.
Next: How to boost your energy, end physical exhaustion and more...