system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How can "power naps"(10-30m) be more effective than longer naps? (1-3h)
gpt
A Power Nap ends before you enter the phase of Deep Sleep.

&nbsp;

 Sleep occurs in four cycles of around 90 minutes each-

+ Light Sleep Cycle

+ Deep Sleep Cycle

+ Dream Cycle

+ Light Sleep Cycle 

*(repeat)*

&nbsp;

If you wake up in b/w a cycle (before it's finished, but after it has started), you'll feel very tired. Which is why you should sleep for either six hours, seven-and-a-half hours, and nine hours.

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The power nap is thought to maximize the benefits of sleep versus time. It is used to supplement normal sleep, especially when a sleeper has accumulated a sleep deficit.