how long between rem periods of sleep
Sleep cycles through these stages approximately 4 or 5 times throughout the night. We typically enter REM approximately 90 minutes after falling asleep. The first cycle of REM often lasts only a short amount of time, but each cycle becomes longer. This is why we need long periods of sleep each night. If we get short periods of sleep, we canât really get through the stages we need to heal and stay healthy. REM can last up to an hour as our sleep progresses. In case you are wondering, if you feel like a dream is taking a long period of time, it really is.