Sleep Stage Non Rapid Eye Movement (NREM)
Definition - What does Sleep Stage Non Rapid Eye Movement (NREM) mean?
There are four stages of non-rapid eye movement sleep cycles (NREM) that must occur before the body shifts into REM sleep, with each stage lasting approximately 5-15 minutes. The deep cycles of NREM sleep accomplish reparative growth in the body, including in the tissues, bone and muscle of the body and bolstering the immune system. This is important to occupational health and safety because NREM sleep restores the body, allowing for safer workplaces and more productive and efficient employees.
WorkplaceTesting explains Sleep Stage Non Rapid Eye Movement (NREM)
Stage 1 of NREM sleep is considered light sleep, where it is easy to arouse the person, a state between sleep and wakefulness lasting about 5-10 minutes. Stage 2 is still considered light sleep, but the body is preparing for deep sleep, with the heart rate and body temperature declining. Stage 3 and 4 are considered deep sleep, where it is difficult to arouse a person and they are often disoriented if awakened during this stage. The final stages of sleep are deep and restorative with delta waves occurring in the brain. Blood flow increases in order to regrow and repair tissue, while hormone and energy supplies are restored. With age, NREM sleep declines to an average of 30 minutes to 2 hours of restorative nightly sleep.