A note on how to think about time asleep 2021-01-21 20:11:11

Rapid eye movement (REM) sleep is a critical stage of sleep that is believed to benefit learning, memory and mood.

REM sleep does not occur evenly throughout the night; most of it happens in the second half of your sleep period.

Not all minutes of sleep are created equal.

To get 7 out of 8 hours of sleep is not to merely give up 12.5 % of sleep, you're actually losing out on an even larger portion of REM sleep that you would otherwise get.

So next time you debate about sacrificing 30-minutes or more, understand that you're giving up a lot more quality rest than you might think.
Hypnogram showing distribution of different sleep stages throughout evening

William Liao

The foundational question and when to pause Go for it
 I’d actually forgotten about this observation until I read your post! It’s something I routinely try to communicate to friends and colleagues - the logic of waking up early to gain an extra hour almost never adds when you think about the cascading effects less sleep has on your ability to perform throughout the day. 
2021-01-21 22:13:21