Hi, I was wondering what others' thoughts were on quantity (total time) versus quality (% of deep+REM sleep).
I've been using a Misfit Ray tracker for several months now and it's quite accurate (admittedly anecdotal) when it comes to measurement of light and deep (including REM) sleep phases.
One thing I have observed is that my percentage of deep sleep typically goes down the longer I sleep... beyond 7 hours or so.
It's a mystery to me why this is. I suppose on some level, when I know I'll get up earlier, I tend to sleep better. Conversely, when I don't have a particular wake up time, such as many weekends, I am more restless.
I will add that, as a professional in my 40s, I have a fair amount of stressors going on. But, I train for triathlons which results an a ton of cardio exercise, a very effective counter to mental stress. I've also found that Magnesium supplementation helps sleep quality.
A couple recent examples:
Of these, I feel far better after 6h18m of high quality sleep, following some initial grogginess. I am mentally sharp and physically refreshed.
So I am thinking that above some threshold, say 6 hrs (for me), quality trumps quantity. 7 hours of sleep seems to be my sweet spot based on months of data.