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calliex

macrumors 6502
Original poster
Aug 16, 2018
492
241
Pittsburgh, Pa
After updating my Ultra II Apple Watch and Phone 15 to ios26 Vo2max dropped from 36 to 32.
It has steadily come up from 34 to 36 until today after a 3 mile run ended up at 32hm
I am 75 and have been working all summer to get to go up.
I am assuming a algoritm change.
Any one have other thoughts
 
You should talk to this guy: https://forums.macrumors.com/threads/change-in-vo2-max-since-upgrading-to-watchos-26.2466427/

Mine also continues to go down, from 54.7 before the update to 51.2 today. As it's still pretty high and I'm winding down a training plan for a half-marathon on Sunday, maybe? It could also be that my new watch is capturing more heart-rate data than my old Ultra was? Or, as you say, Apple has improved the computation with watchOS/iOS 26?
 
my VO2maxI have been steadily rising during this summer from 34 to 36.4. Day after the update I went a long 5 mile walk/jog and got the 32 reading. It is still good for my age and stays at 32 for my last couple of runs. Just disappoint.
 
You should talk to this guy: https://forums.macrumors.com/threads/change-in-vo2-max-since-upgrading-to-watchos-26.2466427/

Mine also continues to go down, from 54.7 before the update to 51.2 today. As it's still pretty high and I'm winding down a training plan for a half-marathon on Sunday, maybe? It could also be that my new watch is capturing more heart-rate data than my old Ultra was? Or, as you say, Apple has improved the computation with watchOS/iOS 26?
Down to 50.6 today. It goes down every day. As I said, it was 54.7 on the day I installed the OS 26 updates, just 17 days ago, and 54.5 the day before I got my Ultra 3.
 
I would say it has to be a change in the algorithm. My phone did a recalibration a week of so and it went up about 2 points. It did go down 4 points with the new phone and S11.

I don't pay much attention to the number, you want to watch the trend.
 
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