When you feel sleepy during the day, it is common to hold it in or try to wake up. However, if you take a proper nap, it is better to take a nap rather than take caffeine such as coffee because it improves your life efficiency. Sleeping too long can cause fatigue and break the biorhythm, so it is effective to take a nap for 10 to 20 minutes if conditions allow. [Enhancing his memory] Napping hel..