Too long nap time will affect the night sleep time, and there will be dizziness, mental inattention and other phenomena. Too long nap time may affect the night sleep, the normal night sleep time is 6 to 8 hours, too long a nap time leads to shorten the night sleep time, insomnia and other situations, the next day appeared to be tired, irritable, spirit, etc., affecting the normal study and work. Too long nap time is easy to enter a deep sleep, the more you sleep, the more you want to sleep, there will be fatigue after waking up, dizziness, mental inattention. Napping too long will also affect the appetite, do not want to eat. Normal nap time is about 30 minutes or so, to avoid too long nap time, you can appropriate exercise, relaxation.