Scientific Review - Many Garmin Watches Extremely Inaccurate

If you are getting no deep sleep at all that might suggest sleep apnea, as if you are getting over 14 apnea per hour then it will prevent deep sleep. A red flag to go with that is if you are getting up more than 2-3 times during your sleep to urinate as if not getting deep sleep your brian isn't producing chemicals which suppress urination (note might be due to other issues like infection, old age etc - so its only a red flag to discuss with doctor to discuss getting tested at a sleep clinic).

I use a ResMed Air 10 with full face mask and have it set to 12bars pressure as am severe obstructive apnea (over 60) - and when my mask leaks and have apnea close to or over 14 apnea per hour per my mahcine then can see the impact on my sleep score.

Whenever I have a bad sleep score I check my ResMed results and every single time there has been an issue. I have never had an issue on my ResMed results and not seen it reflected in my first beat sleep tracking. Unfortunately cannot confirm with other sleep tracking as had just changed to a first beat sleep tracking watch when I got my CPAP machine so can't confirm on watches outside of that.

if you have partner ask them if they think you stop breathing while you are sleeping; do you urinate 2-3 or more times each night during your sleep period; do you always feel tired and have to take naps (this is only after you have had issues for a while). 

If you think you have sleep apnea please do discuss your issues with your doctor and see about attending a clinic as if you do have issues with sleep apnea, going onto a CPAP machine (if you can get used to it) can be life altering.

Pluse Ox at night - don't bother - far too easy to trap you wrist you are wearing it on so that you get gaps in your recordings and its not really accurate enough to provide any discernable benefit for sleeping.

If you want to track it rather do a manual reading first thing in the morning when you wake up prior to getting out of bed, as will reflect your current oxygen levels in your blood. You can then look at that trend over time.

Thanks for sharing. I don't think I have it, I was just curious how it is diagnosed. I never go to toilet once I am asleep, and I don't wake up during sleep at all (my partner does go to toilet during the night (but only once) and she wakes up an hour earlier than I do, but I can't remember noticing either while I sleep). Also, I rarely sleep / nap during the day. Maybe some days if I go to office and was a bit stressful day. I also exercises everyday, but this is probably true for everyone on this Forums :D

I asked my partner if I snore during the night and she says that sometimes sI do, but so does my partner, but neither of us would describe it as 'loud' snoring, but almost like 'louder breathing' .. noone would wake up due it. 

What I think I might need to get checked up in future is about my 'nassal passage', I feel like I am speaking too much from 'nose' and for example, if I physically 'move my nose / push up', it feels easier to breathe. Could be some weird nose deformation I have and probs fixable with some surgery - but will have to see about that. Maybe I just have clogged / stuffed nose all the time. 

For me it does not matter how many versions the review was behind. Let me explain myself. Garmin did not measure the accuracy of their sensors before selling a product? If yes and they found it acceptable then something is wrong, if they did not then again something is wrong.

I can't remember how many Apnea per hour you were recorded at, but I remember think you were pretty much border line, in which case its likely that you were getting sufficient deep sleep so that you weren't overly impacted by fatigue and weren't getting the urination red flag.

Hm, what is this Apnea per Hour? I haven't done any tests like that to be honest, or is this Garmin thing?

welcome to the lovely world of tech. While a lot of stuff is tested these days most tech items have so many features that they come out effectively in beta versions to match marketing drop dates (don't forget it was already 1 year later than usual drop due to Covid and its relating chip shortage) which does mean we tend to see a lot of updates for phones, watches etc - that is life, cause nothing comes out in its final version. today most tech items when they fail/ come to end of manufacture determined life often still aren't at final vesion as so easy to update and make changes.

So yes while they had measured the sensors etc its entirely possible there were issues etc with bugs and lack of larger testing pool until they had enough user data to tweak the algorithms.

However you are also discounting that it could also have purely been due to the user testing, as there is minimal differences between Epix and Fenix and he effectively restested the Fenix after testing the Epix and got very different results which I think were on the same firmware. This was pointed out to him, so he eventually got around to retesting the Fenix at which point it was on a new firmware version and yes a marked difference. But whether due to his lack of proper scientific testing methods (despite what his name implies which I personally consider false advertising) or whether it was due to firmware as now scored higher than the Epix, not the same - who knows. Effectively at the very least could have run both with new firmware on same wrist or done with Epix on old an Fenix on new, then another set. But as stated already pointless as 5-7 data polints to make an analysis is not nearly enough, especially when your baseline device isn't accurate (based on his own scoring methods he only considers above 95% to be accurate so shouldn't even be using this EEG device, as a side note scientific correlation considers over 0.9 as excellent and over 0.85 as very good, below 0.8 is not a good correlation).

So really his reviews are pretty pointless but do love to watch them as find his bias fascinating.

Sure, I completely understand what you are saying. The reason I was thinking of the Marq Gen 2 was solely (mostly) on the reason of getting maximum TCO out of a Garmin product, from an update life cycle perspective. It seems that all of these devices have a life of about 3 years, then they are essentially static (from update perspective) after that. The Epix is already well into the first year. Plus I like the look and build of the MARQ device.

My past buying patterns have always put me in the buying position of dropping big $$ on a device well within its first year, and sometimes a little later. Then something new comes out, and I end up buying again, with big $$, in a shorter time frame. When you factor those spent $$, and the time remaining for the update cycle, then buying the MARQ (or any brand new watch) when it drops makes better sense for me… as long as I keep it for the full update life span.