How to Measure Sleep Wake Cycle
- 1). Make sure that a working clock is set near your bed and that you can see it from the position in which you usually fall asleep. Turn off the alarm if it is enabled.
- 2). Look at the clock as soon as you feel yourself falling asleep.
- 3). Look at the clock again as soon as you wake up.
- 4). Divide the number of hours you slept by 90 minutes. That figure is the number of complete cycles you have slept. For example, if you fell asleep at 11:00 PM and naturally wok up at 8:00 AM, you have slept for nine hours. Ninety divided by nine is six complete cycles of sleep.
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