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jonplackett

I get pretty obsessive with stats, health stats especially

But I’ve never understood or cared much about my blood oxygen reading.

I’m curious - did anyone out there really use that stat? If so what for?

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I recall at the height of COVID, it was advised to keep an eye on one's blood oxygen level

The problem there was that, unless you were already clearly seriously ill, your blood oxygen did not drop. It was not diagnostic.

Early on there was a lot of concern about 'happy' hypoxia where your blood o2 was dangerously low but people didn't feel critically ill. I'm not sure where that ended up clinically/evidentially as things moved on though.

Sometimes even clearly seriously ill people don’t go to the hospital. Especially in the middle of a pandemic.

Some friends and I use it all the time when flying at elevation and for training breath holds for free diving.

Was useful for the couple of times I had covid too.

Which is to say it’s very useful to me a few times a month. I wouldn’t go out of my way to buy a Massimo watch for the feature though.

It’s interesting for people who live at sea level but do a lot of mountain activities on weekends.

High elevation seems to have a big effect on blood oxygen but does vary person to person. It’s interesting to see one’s own response. I get why my sleep is shitty the first couple days at altitude after seeing the numbers.

I use an oxygen generator in my airplane when oxygen is required by the FAA (above 12500 ft for 30+ minutes, above 14000 ft at all). This has a visual flow-meter on it, but oxygen generators have an additional failure mode where gas is flowing, but is not oxygen enriched, so regular blood oxygen monitoring makes sense. I also monitor when above 12000 ft but before oxygen is required, to decide if I want to get on it early. I actually use a fingertip reader as my primary, but upgraded my Apple watch to an oxygen-capable one to have a backup instrument.

I took one high altitude mountaineering. It was interesting seeing how low the O2 goes and how much using bottled oxygen effects it.

Mine dipped to below 80 when I was sleeping.

Turns out I needed a CPAP, which was confirmed by a complicated medical contraption I had to sleep with.

It helps to track VO2Max if you’re into cardio. I’m assuming the watch can no longer measure it.

Most smartwatches estimate VO2Max using other data (mainly how fast you run/ride, your HR, and your weight). Blood oxygen level is not used for that.

I'm pretty sure VO2Max on the Apple Watch is measured using heart rate and not blood oxygen. It uses some algorithm to measure how fast your heart rate should be when you walk/hike/run.

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