Deep Sleep

Deep sleep is a state of sleep during which the brain is given time to relax and the muscles and immune system are given time to rejuvenate. It consists of stages three and four of NREM (non-rapid eye movement) sleep and can also be called slow-wave sleep. It is difficult to wake anyone from this stage of sleep. If you do not receive enough of this deep sleep, this is the most common cause of sleep deprivation and will need recovering in order for you to feel more refreshed. If you are finding that your sleep is often disrupted, e.g. you do shift work, then you must find larger amounts of time to sleep so that your body can enter into a deep sleep.