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The Sleep Cycle

The Four Phases of Sleep

By

Hugo Rivera Gets His Sleep

Hugo Rivera Gets His Sleep

Photo Credit: Lina Rivera
When we deprive ourselves of sleep, there is a delicate cycle that we disrupt. Let me now share with you that cycle:

Phase One: Phase one begins as soon as the sun sets, when the pineal gland starts to release melatonin, a hormone released in the absence of light and responsible for making us sleepy. When you lay down in your bed at this time, your muscles relax, heart rate and breathing slow down, and body temperature drops. The brain also relaxes but still remains alert. If you could look at the wave patterns being generated by the brain, you would see a change from the rapid beta waves of daytime to slower alpha waves. When the alpha waves disappear, replaced by theta waves, the sleeper has tumbled into the sensory void called stage one sleep. In this stage, the sleeper is unable to sense anything.

Phase Two: Phase two occurs a moment after phase one and in this stage the sleeper lays still for about 10 to 15 minutes.

Phase Three: After Phase two is over, the sleeper falls into a deeper sleep. During this stage, the sleeper falls deeper into phase three which lasts about 5 to 15 minutes.

Phase Four: With a maximum of 15 minutes spent within the phase three cycle, the sleeper then falls into yet another relaxed stage called phase four, lasting a half hour or so. In stage four, the eyes move back and forth very quickly in what's called rapid eye movement, or REM. This is the point at which the first dream occurs. After this dream has ended, the sleeper then goes right back to phase two and starts the whole process over again. These processes repeat themselves about five times during the night.

Sleeping Requirements
Sleep research indicates through studies that the average sleeper will sleep approximately 8 hours and fifteen minutes when uninterrupted. During this research, there were no alarm clocks or disturbing noises to interrupt normal sleep patterns. 8 hours and fifteen minutes is believed to be the ideal physiological amount of time that the body requires for proper sleep time.

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