Depending on the Garmin, it’s probably because Garmin actually takes elevation gain and heat into consideration with vO2 max estimates. Apple does not. So if you’re running in really hot weather or on a steep route, it thinks you’re less fit.
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VO2 Max underestimated consistently
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Depending on the Garmin, it’s probably because Garmin actually takes elevation gain and heat into consideration with vO2 max estimates. Apple does not. So if you’re running in really hot weather or on a steep route, it thinks you’re less fit.
Same here. Maybe I should forget about the VO2max score as well.
In fact, I was planning to gift myself a full physical test for my birthday, but didn't get to it.
Perhaps next year ;-)
My apple watch and Garmin are pretty much the same for v02 max, garmin has me at 56 and apple is 55.2.
I feel the same - slow easy runs and it goes up. Tough intense runs and it goes down 😵💫
Just coming here to complain about this measurement, lol. My VO2 Max is 27.8, which is low. So you’d think my heart would be overworking itself to get oxygen to the rest of my body, right? Nope. Average walking heart rate for the month is 87, and my average resting heart rate is 58.
I investigated this in the past because I felt the watch's VO2Max was too low. My watch shows 40.3, which is in the top 10% for my age group, but I think it is actually higher based on comparisons with others in my age group. Getting a valid test is expensive, but there are other alternative measures. See: 3 Ways to Measure VO2Max. When I measured it using the Rockport test described in the article, it was very close to what the watch reports, so maybe Apple uses a similar algorithm.
I think it uses heart rate on runs quite a lot. Here during winter my Ultra can sometimes lose my heart rate during runs and when it comes back it can be way too high. When my arms get cold, the watch can have a tough time reading it correctly. Usually run with a Polar H10, but when wearing a hydration vest for the long runs, I need to skip that.
On my long runs where it looses my heart rate and reads a way too high one, my VO2 Max drops. On the following days with the strap and the usual lower heart rate (can even be same tempo) it will rise again.
Would love Apple to be a bit more transparent to how it calculates it.
On my long runs where it looses my heart rate and reads a way too high one, my VO2 Max drops. On the following days with the strap and the usual lower heart rate (can even be same tempo) it will rise again.
Would love Apple to be a bit more transparent to how it calculates it.
I don't think that this satisfies your request for transparency, but Apple published a relatively complete white paper showing how their model compares with measurements taken using PET tests.
My current VO2Max is 53.7, and I've always thought it's measuring me high. That said, my last month's average resting heart rate is 44, walking heart rate is 77. So, who knows? (I am uninterested in validating it with a real test.)
Late replay but anyway.
If you average walking heart reat is at 87 bpm you are walking slow not taxing your self and thus get a "low" VO2max reading.
I normally do 2-3 runs each 8-10 km a week (well not for the last couple of months due to a bad injury) and when walking (as walking for exercise) I normally average 110 - 120 bpm. My resting heart rate is at around 50-55 bpm (sleeping heart rate at 42-47). Of course the numbers I give you above for myself is pre injury and I've lost a lot of my fitness the last couple of months because of not being able to be as active due to the injury I got.
As I said in a post over a year ago in this thread, really don't use absolute numbers from the watch for VO2max use them more relative to how you develop when exercising.
In your case I can tell by the info you give me that you do get a low number because you are actually not getting that much exercise from your walks (even if any kind of physical activity is better than no physical activity). And that's actually fine, but if you want better values you have to push your self harder when on walks
Same, to get as low as 87 when walking I’d have to be quite slow: I get around 110 bpm when walking about 15-15.5 minutes/mile (about 9:30/km), which is a brisk but not hard pace. I typically walk for 45-60 minutes at a time. My VO2max estimation for walking is over 40, 27.8 is what I would say is basically someone who doesn’t exercise much at all. Your heart doesn’t need to work hard when you don’t push it. What’s your HRV?
Just for additional context, the walking average is not the average during walking workouts. It includes any movement during the day the Apple Watch considers “walking”.
When I specifically do an outdoor walk, it is a bit higher. I’m checking recent walks, and while it’s on the higher end of “brisk”, I see one where it’s 106BPM at an 18’29” pace. Another one that’s 18’51” at 98BPM. My sleeping heart rate went down to 45 last night, sometimes it goes into the high 30s.