I have always wondered who is more precise, the VO2Max Apple calculates with the watch or the VO2Max Runalize calculates. I run with the apple watch and stryd. Record with the iSmoothRun app.

A couple of days ago I did a VO2 Max test in a top notch lab which also measures professional athletes. I ran on a treadmill with mask measured calories, fat oxidation and whatnot. I recorded the run with stryd on the indoor setting.

My overall VO2 max according to apple watch: 49
My overall VO2 max according to runalize: 41.32
My VO2 max according to the lab run: 50.3
My VO2 max of the lab run according to runalize: 41.9
Apple watch didn't do a VO2max for that run, because it was less then 20 minutes.

This massive discrepancy between runalize and apple has always been that way and I never knew who was right, but at least both agree on trends.

But now seeing the lab test I'm shocked that it is in fact runalize which is so massively off that it practically loses all credibility.

While I ran I could see my running power on the treadmill and compared it to the stryd measurement and it was pretty much ok. Also HF was pretty much the same as measured by the lab-device.

So bad data really is not to blame here. Especially not since the Apple watch had been doing a better estimation for a long time now, even though it didn't always calculate power itself and it doesn't use the stryd measurement for its VO2 max estimation, but only what it measures on the wrist alone.

So I wonder. What gives? Can I set a correction factor or something?