I used to use a Fitbit to track my sleep. I noticed that after sleeping very few hours, I’d have more % deep and REM sleep the following night (and less % light sleep / restlessness) often enough for me to notice a correlation. I checked my friend’s Garmin sleep stats and it’s roughly the same.
I wouldn’t give too much weight to the accuracy of this observation (confounding, device accuracy etc). However it just about makes the cut to share it in a comment imo.
I used to use a Fitbit to track my sleep. I noticed that after sleeping very few hours, I’d have more % deep and REM sleep the following night (and less % light sleep / restlessness) often enough for me to notice a correlation. I checked my friend’s Garmin sleep stats and it’s roughly the same.
I wouldn’t give too much weight to the accuracy of this observation (confounding, device accuracy etc). However it just about makes the cut to share it in a comment imo.