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Understanding the 90-Minute Sleep Cycle

Sleep is not just a passive activity where the body shuts down. Instead, it is a highly structured and active biological process that plays a critical role in maintaining physical health, mental clarity, and emotional balance...

What Is a Sleep Cycle?

A sleep cycle is a sequence of different stages of sleep that your body goes through multiple times during the night. On average, one complete cycle lasts about 90 minutes...

The Four Stages of Sleep

Why the 90-Minute Rule Matters

Most people think sleep quality depends only on total hours, but timing matters just as much. Waking up at the end of a cycle makes you feel fresh and alert...

Ideal Sleep Durations:

• 4 cycles = 6 hours

• 5 cycles = 7.5 hours (Recommended)

• 6 cycles = 9 hours

Tips to Improve Your Sleep Cycles