The first stage of sleepis very light sleep, and constitutes 4-5% of a typical cycle. Muscle activity is slowing down, but there can be occasional twitching. The eyes are moving slowly under the eyelids. When one sees a person moving about in bed, they are probably in light sleep.
In the second stage of sleep, one’s breathing and heart rate slows. A slight decrease in body temperature occurs. This is still what one would call “light sleep,” and it constitutes a whopping 45- 55% of a typical monophasic cycle.
The third stage of sleep is when deep sleep begins. The brain begins to generate slow delta waves, and this stage constitutes 4-6% of a typical cycle.
The fourth stage of sleep is very deep sleep. Breathing is rhythmic and muscle movement is very limited. The brain is producing delta waves. 12 – 15% of a cycle is given to stage four. Being waken up at this point will produce extreme fatigue and confusion. Stage four sleep is non-cholinergic so if you do dream during this stage you will not remember.
The fifth and final stage of sleep is REM sleep, which is an acronym for rapid eye movement. Brainwaves speed up and dreaming occurs. If a person is completely still while sleeping, has shallow breathing, and is rapidly moving their eyes under their eyelids, they are in REM sleep.
How deep and consistent our sleep cycle is, depends upon how well we set ourselves up for success for sleep itself. Our evening rituals can greatly determine our quality of rest and, ultimately, our own vitality throughout our day. This week, take note how well rested you feel in the mornings when you wake up.