Bryan Johnson· Author
This is because a low HR reflects a calm, parasympathetic state conducive to restorative sleep.
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This is because a low HR reflects a calm, parasympathetic state conducive to restorative sleep.
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High HR (sympathetic activation) inhibits the onset of deep sleep and keeps the brain/body more alert, whereas low HR (parasympathetic dominance) facilitates the transitions into deeper stages and continuous sleep.
Slow heart. Good sleep. Fast heart. Bad sleep.
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