What Vo2 max results do you obtain with Garmin 945 and Polar H10 (fitness test)?

On the bruce treadmill test at a sports cardiologist at unc, i ended up with 52.x; my garmin consistently has me between 42-45 and the polar h10  at 49. 69 yr old guy, good swimmer, but use elliptical trainers a lot as pretty much nuked my feets with decades of running with a body not suited for running

Hi,

My Running Index is 51, Fitness test is 55 for the last 3 weeks, my FR945 tells me that my VO2Max is 47

Polar fitness test is a marketing gimmick. Basically, it only changes when you change the value of how often you train.

In Polar's materials they boast a mean deviation of 12%. But if you look closer, mean deviation of 12% means, that for each person with accurate result there is another person for whom the result will differ by 24% from true.

Let's suppose you run 10K daily. On 4 consecutive days your GPS watch shows values 12.4K, 11.2K, 10K, 8,8K. Quite accurate - the mean deviation is only 12%. 

>Polar fitness test is a marketing gimmick

So absolutely nothing like Garmin’s VO2 estimate ;-)

Well, if you dive into the Firstbeat whitepaper, you will see that the accuracy of the Firstbeat/Garmin test is claimed at +/-5%. Although this increases to 9% if you don't have an accurate maxHR estimate.

Done during treadmill stress test as port of an extensive cardio workup: 52.x

Polar would often be somewhere in the low 50s...till it broke in my fall..that prompted the cardio workup

Garmin 42-44. The Garmin (vivoactive 3 and Swim2) sometimes decides a leisurely walk with my wife IS a worthy of a VO2 evaluation???

69 yr old male

Well, on my beloved FR-920 I have installed the app VO2 Max Estimator (https://apps.garmin.com/en-US/apps/bdc61482-b5d7-41b6-89ba-00472e0c5def). This app shows me a consistent value between 51 and 52. Also, at the same time, my old (and beloved too) Polar 625x calculates my VO2max at 51 (a static test based on HRV).

My FR-920 was increasing my VO2max (the Garmin one, not the app) from 42 (after I recovered from a broken bone on one of my feet 7 months ago) to the current 47/48. The polar increased the value from 48 to the current 51 and the app from 49 to 51/52. My new FR-945 (since 2 weeks) calculates the same value(s) as the FR-920. 

My experience tells me that Garmin VO2max should be used as a measure of progress, but not as the current valid value. It seems to be too low compared to others methods (I can't probe right now which one has the more accurate value BTW). For more information see the VO2 Max Estimator description (the app is based on a well know paper) and the user's comments (some of them say the same, that the Garmin estimation is too low compared to the app which is in sync with some lab tests). 

I am 46 years old male.

i find it peculiar that my "fitness level" gets evaluated over the period of a month as equivalent to that of an "average" 20 yr old and then an "average 36" year old.