Why this combination? Caffeine blocks the action of adenosine — a compound responsible for the sensation of fatigue. Its effect, however, is limited and begins only about 20 minutes after coffee consumption. This 20-minute window is the optimal duration for a nap, during which the body naturally clears adenosine from the system. As a result, when you wake up, caffeine starts to take full effect and has to counteract much smaller amounts of adenosine. The outcome is significantly greater alertness and readiness for action.
However, remember to wake up after approximately 20 minutes. Oversleeping this optimal moment of arousal may cause fatigue to return even more intensely.
