Pounding back two or more mugs of coffee first thing in the morning will chase away fatigue, but not for long. Researcehers at Harvard tell us that caffeine fights off drowsiness by blocking the buildup of adenosine, a powerful sleep-triggering compound found in the brain. But if you only sip coffee first thing in the morning, adenosine levels, and therefore fatigue, can creep back up by mid-afternoon. Quick Fix: Enjoy one mug of java first thing in the morning, then spread the rest of your caffeine intake out over the remainder of the day. Scientists suggest sipping about 4 ounces (that’s half a cup) every hour until you’ve finished your usual daily dose. A thermos will work beautifully for this task or simply choose an office cup that’s on the small side. The steady trickle of caffeine will dampen the brain’s production of sleep-inducing adenosine, say experts, giving you all-day protection from fatigue.