Sleep duration is never accurate

I don't sleep 10 hours per night. Last night, for example, I know I slept for 1.5 hours because I tried to sleep but couldn't because I kept thinking about the flight I had to take in the morning.

I needed to get up at 4am and was worried I would sleep thru the flight. So I ended up staying awake until at least 2:30am. I even got up and walked around for a little. So I had maybe 1.5 hours of bad sleep yet my watch gauged I slept from 10:11pm thru 8:39am.

This is just today's example but the majority of the time it measures any couch potatoing at night, low heart rate or little movement as sleep. Without direct knowledge of how Garmin measures sleep, I assume it's not a sophisticated measure in the slightest.

0 ajwms2222 over 2 years ago

Monday Dec 27 - 11h 1m

Sunday Dec 26 - 14h 43m

That's not true @ all.

0 drmrboss over 2 years ago

There is no way a wearable watch can detect whether you are sleeping or not accurately. As you mentioned above, the watch can only detect your hand movement and heart rate ( pulse oximeter in certain models) and predict whether you are sleeping or not. Such prediction is extremely unreliable as you see in your case.( A kind of marketting gimmick).

An accurate machine to detect your sleep is polysomnography. They record your brain waves, the oxygen level in your blood, heart rate and breathing, as well as eye and leg movements during the study.

0 4582235 over 1 year ago

The watch can record afternoon rest/low activity/inactivity as sleep. A common problem unfortunately!

It can be corrected on a case by case / daily basis by editing the sleep stages timeline in Garmin Connect and re-syncing watch.

The sleep settings in the user profile 'Normal Bed Time' and 'Normal Wake Time' just tell the watch when to activate sleep mode - turning off notifications/dimming screen etc. It has noting to do with when sleep can be recorded.