system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5 How we can sleep in a position that causes debilitating pain when we wake up, but don't notice at all while we sleep?
gpt
While your body sleeps, it alternates between REM (Rapid Eye Movement) and non-REM cycles. REM sleep is where you dream and the body essentially recuperates from being awake. During this cycle. Your body is paralyzed, which prevents you from feeling pain or discomfort at all, so if your body is at an awkward angle moving into this cycle, you will not wake from the pain, but when you move out of the cycle the pain will likely wake you up.


EDIT: just wanted to say thank you to all the people for the awards, and to remind everyone that every person is completely different, so your personal body very likely does react differently while sleeping, and thats 100% ok!