Getting enough sleep is vital for maintaining bodily functions and general health; lack of sleep can affect your mood, energy and stress levels. The National Institute of Health recommends seven and a half to nine hours of sleep per night in order to achieve high levels of functional activity.
What is the Sleep Wake Cycle?
Scientific studies have found that the brain goes through different periods of activity during sleep. These characteristic patterns of activity are known as REM (rapid eye movement) and non-REM. The stages of REM and non-REM sleep form a sleep cycle. Each cycle lasts for approximately 90 minutes and repeats four to six times during the night.
Non-REM Sleep: The stages of reaching deep sleep
- Stage 1: Transition
Your eye movement slows, muscle activity reduces and you are easily awakened
- Stage 2: Light sleep
Your eye movement stops, your heart rate slows and your body temperature decreases
- Stage 3: Deep sleep
Your brain activity slows as your blood flow is directed away from the brain to the muscles
REM Sleep: Dream Sleep
This occurs 70-90 minutes after falling asleep; the phase when you actively dream. Your eyes move rapidly, your breathing shallows, your heart and blood pressure increase and your arm and leg muscles become paralysed.