Lies, Damn Lies, and Fitbit Warnings

I've been wearing the new Fitbit Versa 4 for a week or so, but I can't really review it yet ... because it's telling me things that may or may not be true. If they're true, I guess I have to highly recommend it. If they're false, well, not.

Let me go through the things I really like about it first:

• A larger and more intuitive display than my previous fitness tracker, the Amazfit Band 5.
• The ability to actually answer phone calls and talk right from my wrist (as long as my phone is close enough by to be linked/synced with the smart watch).
• I can talk to Alexa through it (for example, when I'm nearing the end of my morning walk, I can say to my watch "turn on the espresso machine" and my morning shots will be just about brewed by the time I walk in the door).
• On the "sedentary alert" front, instead of just buzzing me at me if I don't move often enough, it actively alerts me at 10 minutes before the hour as to how many more steps I need to take to meet my minimum 250-per-hour goal (and lets me set the morning start and evening cut-off to such alerts).
• Once I replaced the default silicone band, very comfy (I had to do the same thing with the Amazfit).

I'm not inclined to complain when a research study offers to send me a $200 smart watch.

BUT!

There are certain functions that seem to be behind a premium paywall that were free in Amazfit's app (for example, on-demand blood oxygen measurement). They're offering me a six-month free trial, but I'm a little bit against the whole idea on principle. Someone paid $200 for this watch, and then I'm supposed to pay more to have it give me information that I know it's collecting already?

I mention blood oxygen because, even though it doesn't seem to be set up to let me check mine, it's certainly tracking the info, as on a couple of different mornings it's informed me that my blood oxygen had some "high variability" during the night, and that this might be an indicator of e.g. sleep apnea. And it does give me a running average on blood oxygen ... an average which is low (94-95%) compared to what the Amazfit always indicated, what I've always shown using my little finger clamp pulse oximeter that I can't find at the moment, and what I was told I was running when I recently underwent a pulmonary function test at an actual pulmonary medical office -- 98-99%.

I've also previously used other sleep apps on my phone that listened to me through the night and indicated no breathing problems (they would detect a snore maybe once every week or two, and record it so I could listen to it -- it would be literally one or two little honkers, then back to quiet sleeping). The Amazfit's sleep analysis also gave me a clean bill on that. And my wife says she hasn't noticed any snoring, snorting, or other weird sleep breathing. Which she would notice. So I'm skeptical that the blood oxygen measurement is accurate or that it means what the warning says it could mean. I wonder if I'm fidgeting with the band in my sleep or something, causing the measurement apparatus to be inaccurate?

More worryingly, on two consecutive mornings, I woke up to find out that the Fitbit was telling me a fib, over and over. A fib as in afib -- atrial fibrillation. Not a diagnosis, but multiple warnings saved overnight that my heart rate variability indicated the possibility of afib.

It's been a few years since I did a stress test and echocardiogram, but those were clean (other than discovering that my heart is "wired backward," aka "left branch bundle block," causing EKG readings to make doctors blanch and think I've had a damaging coronary). My doctor listens to my heart every 3-6 months, and is on high alert about it since she knows my entire family is prone to heart problems. And I'm pretty sure the pulmonary thing included a lead to monitor my pulse for any regularities while I was blowing as hard as I could into a mouthpiece, etc.

But, of course, I am still worried and will discuss this with my primary doc next month when I go in for my next visit.

I think that the Versa 4 is probably either over-sensitive or inaccurate. But I don't know yet.

If it turns out that I have sleep apnea and/or afib, I'll obviously be grateful to Fitbit for letting me know about that. If I have neither one, my actual review will reflect those warnings as value-reducing unnecessary alarm.

"I might as well comment on general health while I'm at it" update, about 5:15pm -- So, I quit smoking a month and a week ago ... since which I've lost about a pound and a half of weight. Why? Well, even though I've felt so non-energized that getting on the bicycle and going anywhere at all distant seems impossible, I have been walking at least 10,000 steps per day, and knocking off of food, caffeine, and nicotine (I've continued using On! nicotine pouches, but am down to a few a day and only a 2mg dosage per pouch) at 6pm, and drinking at least two liters of water per day, replacing a lot of my previous diet soda intake. I've also been doing some light plank workouts, usually a couple of sets of halos with my 35-pound kettlebell, etc. So I'm not physically inactive. I feel like I'm getting somewhere. And speaking of the quitting smoking, this is the second time I've done so for long enough to notice that at a certain point I get a "productive" cough, presumably stuff coming out of my lungs that smoking put there and kept there over the years. I wonder if that might be clogging up my breathing every once in a while at night and causing the blood oxygen/heart rate anomalies?