Stage 3 NREM, also known as deep sleep or slow-wave sleep, is the deepest stage of sleep. It is the part of the sleep cycle that allows us to feel refreshed in the morning. It is also the stage of ...

A good night’s sleep isn’t just about the number of hours you log. Getting quality sleep — the kind that leaves you feeling ...

Deep sleep is the restorative stage of sleep. During this stage the body undergoes tissue repair, the immune system is strengthening, and human growth hormone is released. “For kids, this stage of ...

Your sleep cycle includes light, slow-wave, deep, and REM sleep, which repeat throughout the night. To get restful sleep, you need to spend the right amount of time in each stage of the sleep cycle.

A chart on the same page lays it out ... we’ve been through the other stages, and we cycle through these stages all night. Usually REM sleep is fairly short during the beginning of the night ...

Learn more about the importance of sleep. Only the last two stages of sleep ... ideally going through four to five sleep cycles. »Here's how to calculate how much sleep you need.