VO2Max measurment

There is no published answer about whether the weight is used for the VO2 Max calculation before it is divided by weight for benchmarking purposes. Since the VO2 Max model links physiological cost  (VO2 linked to HR/HRV) to output (pace), your weight is definitely a factor since the heavier, the harder it is to reach and maintain a certain pace.

Jan Chodura said:

if the absolute oxygen uptake remains unchanged.

Since weight may not be a linear factor in the physiological cost model, the decreased in cost due to lower weight might not be strictly be neutralized by decrease in the weight denominator when your normalize VO2 Max.

Jan Chodura said:

However, my VO2Max has only increased from 48 to 50 ml/kg/min.

This is already a decent increase for 2 months. Depending on your age and your body ability to sustain the cost of training, there is a natural limit for your VO2 Max, so you will hit a plateau.

"Indeed, a beginner may increase his/her fitness level during 4-
10 weeks of successive training by up to 10-20% [18-19],
although even 44% increase in VO2max in ten weeks has been
reported for persons with average aerobic fitness, by using very
high-intensity interval training [20"

https://assets.firstbeat.com/firstbeat/uploads/2017/06/white_paper_VO2max_30.6.2017.pdf

This question has been asked quite often. The answer is, we don’t know. There is the paper of first beat, who claims it is very scientific (but there is no peer review, so we don’t know how accurate it it, or that it is only marketing). Then we have no clue if garmin developers implemented the algorithms described in the paper and we don’t know how well they implemented it (garmin has a reputation of delivering half baked software)

I can share my experiences but I have done that before and garmin fanboys don’t like that.

my opinion:
Go to a sport medical center if you want to know your vo2max.

do coopertests if you want to have a good indication of your vo2max.

use garmin if you just want to quantify your life.

Correct me if I'm wrong, but if everything else is the same, only the weight is different, then the heavier you are the higher your VO2max is. Am I wrong?

Yes, that's my opinion. VO2Max is measured in ml/kg/min – with "/kg" referring to your weight. So, the absolute volume of oxygen remains the same but is calculated for a lighter body. Of course, Garmin watches provide only a rough estimation. But how can I trust these numbers when the most basic factor isn’t taken into account? :D It’s better without such a magically conjured value. Personally, I view all these metrics – VO2Max, lactate threshold, hill performance, endurance – as more like fun numbers than anything else.

I think even garmin wouldn't say that they are accurate compared to a lab test. IMHO for most users it would be enough if we knew it was consistent for us. In other words if its off by some number but its moving up and down similar to what a lab test would.