Have you every wondered why sometimes you feel sleepy when you wake up, and other times not? It turns out that the answer lies in something called sleep patterns.
Your sleep pattern is a cycle of different types of sleep that you experience while you get your 40 winks. Most adults start with something called NREM (non rapid eye movement) or light sleep. During this time, you are prone to waking and your brain waves are rhythmic. REM (rapid eye movement) or deep sleep is the other section. This is when you dream.Curiously though, some of your arm and leg muscles have been shown to lock up during REM. This is thought to prevent you from doing what you are dreaming about.
During the night, you will alternate between these two types of sleep. If you wake up during a period of REM, you’ll feel tired and will probably want to go right back to bed. However, if you wake during NREM, it won’t matter how long you were sleeping for, you’ll wake up feeling completely refreshed.