VO2max Update Indoor

Hi, my VO2max is also updated twice (first some rounding change because I was still seeing 42 but it moved from 3rd cluster to 4th cluster and then it became 43) with a treadmill run in the last days. I guess it is being reported whenever a change is being detected?

Do you guys use any HRM dynamics, footpod or any other accessory? 

It would be good if they start calculating VO2 with treadmill, considering a proper distance and inclination calibration of course.

I had HRM on during all those runs (during both updating runs and no effect runs).

If this is really true, then I hope it is a setting that we can turn off.
I would not like to have my VO2Max updated over treadmill.
For me makes no sense as the effort in the treadmill does not compare with the one running outside.

For the same pace I can get a much lower HR in the treadmill (around 15BPS lower), which would increase my VO2MAX in a non real way.

Mine updated for the first time ever after the same 4 mile treadmill run I've done for years with various Fenix iterations.  VO2nax updated from 45 (from many outdoor readings) to 47.  I used the same treadmill activity I always used and the app said the reading was from today.  Came on this forum now specifically to see if anyone else noticed this very positive change (in my opinion).  

If your watch is calibrated to your treadmill and your speed, pace, elevation/incline are the same as your outdoor run I don't see why your VO2 max (or heart rate for that matter) would be substantially different on the treadmill.  If your outdoor runs are posing additional challenges the watch can't fully account for (like a trail or beach run on soft sand) I'd argue your indoor VO2Max is more accurate or at least more replicable and therefore more useful.

If you use mechanical treadmill I would agree, if you have electric I disagree. Outdoor terrein is not moving itself like it is on electric treadmill.

Hmm maybe the biggest difference is in the treadmill there is no air resistance cos we are not actually moving forward. 

So running on treadmill might be similar to running on an even and rubbered running track, with favorable wind at the same speed we are running.

It is indeed pretty close because of compensating effects

- the fact that the belt is moving under you makes it easier for you to run and many experts recommend to use a 1% of 2% incline to compensate for that

www.verywellfit.com/treadmill-vs-outside-running-which-is-best-3120796

- the fact that there is less air moving around you reduces the cooling effect and makes it harder on the body: some blood flow needs to be redirected to the skin to cool the body therefore requiring more oxygen from respiration.

As we all know, it ends up being very similar, otherwise VO2 Max tests in the lab would not provide an accurate picture. These tests, by the way, typically include an increase in the incline as part of their protocol.

www.verywellfit.com/the-bruce-treadmill-test-protocol-3120269