Weird calculation / estimation of VO2max
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@Tieutieu Thanks for the information. Yes, I always use the HR belt and how could be seen on the screenshot, measurement of both HR as well as distance (GPS data) during my typical interval training is really perfect - congrats, Suunto! However, when returning to VO2max estimates (I know, exact values must be measured in a lab), values given in a standard way by the watch itself are far from values produced by traditional VO2max approximations presented by various sources / methods, giving, however, similar results (e.g. by Cooper, based on 12 minut run or Balke, derived from 15 min run). Furthermore, when watch gives me a VO2max estimate just based on a slow walk with a pace of 11 minut per 1 kilometer, it seems to me really strange…
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@MartinZ I wanted to add that I noticed something similar - a distinct pattern - the easier my run is, with more breaks and less effort overall, the higher VO2max estimation is. When I have a truly good performance in my opinion, my VO2max estimation is always the worst.
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@sky-runner @MartinZ absolute VO2max estimates by wearables were scientifically shown to be not really accurate. The underlying algorithms try to estimate your VO2max by looking at how fast you can run at a given intensity. Then they look at databases that correlate the estimated race time to a VO2max value. This correlation though is pretty individual.
The correlation between heart rate and pace is also often not linear at very low speeds/walking, leading to values that are not in line with faster runs.
Also when you take breaks and pause your watch, your average heart rate in the end is lower while your average pace stays the same. Then the algorithm thinks your are able to run faster at a lower heart rate/intensity and gives higher VO2max values and race predictions.
Also running with a lot of elevation does not really work as in that case speeds are low while intensity is high.You can though use the development of the predicted VO2max to observe trends in your own training status as your individual correlation is quite robust if you compare the same runs or maintain similar training patterns.
FYI: if you lower the heart rate value between Zone 4 and Zone 5 the values will instantly go down as then the algorithm thinks you are closer to your maximum effort. So keep your zones the same if you want to observe trends.
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@brave_dave I don’t think modern watches use pace vs. HR equation to estimate VO2max. It should be either grade adjusted pace or perhaps running power, which is based on the accelerometer data. That’s what Garmin indirectly confirmed when they announced VO2max changes to support trail running.
In my experience with Garmin, many times, estimated VO2max increased after running a gradual uphill if it was at a runnable grade. But a very steep uphill that I had to hike often had an opposite effect, which pointed to the formulas calibrated for low grade runnable terrain. Correspondingly Garmin’s grade adjusted pace feels horribly wrong on a steeper terrain.
Overall, I think that Garmin does a better job at estimating VO2max. Garmin only considers a sustained effort that lasts over certain duration and where you HR exceeds 70% of max HR or something like that. With Suunto the opposite seems to be true.
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@sky-runner yes, you are completely right. They probably use NGP but even that is an estimated compensation that does not work for everyone and also not on every terrain/slope.
Definitely, separating trail running and normal running is a must and also take out walking activities. Also manually excluding activities where you know that they aren’t reliable would be really nice.
I also asked for these feature in multiple forum posts but I don’t think Suunto reads along or cares. -
@MartinZ I think that your numbers are incoherent. According to you Cooper test, your VMA should be around 12.5km/h but you are supposed to do long repetitions at 16.2km/h. And for those repetitions, you are not reaching your HR maximum which is 189 (did you really run at 16.2km/h?). 16.2km/h is 130% of your VMA! No way someone could make 5 repetitions of one minute run/one minute rest at this speed (130% VMA).
For example, Kipchoge VMA is 24.5 km/h. So 130% is 31.85km/h. And the world “record” of 500m is 1 minute and the speed 30km/h. Despite being one of the best runners of all time, I don’t think he would be able to beat the 500m world record 5 times in a row with just one minute rest in between.
In addition, the Cooper test is known not being a very good test. It is way too long. Half Cooper is better to give you an estimate of VO2Max.
In addition, you should probably also test your maximum HR and correct it if necessary. This probably would give you more coherent results.
But, even if you numbers are finally correct(ed), and because of the reasons explained in the other posts, the estimation of your VO2max by your watch will remain an estimation. -
Why being so caught up by snake oil numbers? Run a race, and then another one after a while. If your result improved, you are good and your training is on point. Otherwise get back to the drawing board. It’s very very simple. No need to spend countless hours on what’s completely irrelevant on a race day. If I were so much into numbers, I’d at least bought myself a lactate meter.
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@LGoSo Thank you very much for your info. All the underlying data for my complaint regarding the strange estimation of VO2Max are in the top of this page, on a screenshot with a result of Cooper test on the left side and a table converting distance run at 12 min to a respective VO2 max level on a right side. Screenshot below relates to another running activity (HIIT) and it is just showing that both the key inputs for the VO2 max estimation (i.e. heart rate and the distance achieved were measured with a very high accuracy, in case of heart rate using HR belt). The belt was of course used also in the case of realized Cooper test with data provided on the screenshot on the top of the page, furthermore, this Cooper test run was also made on a straight road and not on athletic stadium, just with an aim to maximaze accuracy of the distance measured. It means, the input data were highly accurate and the problem is just with a calculation / estimation of the VO2max within the Suunto Vertical watch. Cooper test (SuuntoPlus app) shows 44 (which correspond also to other VO2max estimates made by me manually using more different methods), whereas Suunto Vertical general estimator shows 46.1 for the same (!) activity (could be seen on the screenshot as well) and even higher values for almost all other activities I have made. Everything above 44 looks really strange in my case, out of my capabilities.
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@MartinZ I think you don’t understand what we all want to say…all absolute Vo2max estimations are inaccurate/useless! Also your Cooper test tables or Suunto App results.
If you do a proper Vo2max lab test and you run a cooper test or any race afterwards, you probably won’t get the same results as those tables tell you! The correlation of Vo2max and performance is very individual and depends on a lot of different factors. Mental strength, running economy, environmental factors…
That’s why you will also find different Cooper test vs.Vo2max tables.But if this is already so inaccurate then how accurate do you expect an estimation to be, that tries to predict your maximum possible performance based on intervals or slower runs and then uses this as input into these Vo2max tables?
If you want to track your performance, track something accurate like race times or cooper test distances!
Race times are 100% reflectors of performance and therefore way more accurate than Vo2max values. That’s also why there is no World Record for highest measured or estimated Vo2max
FYI: @LGoSo is completely right. 16,2 km/h or 3:42 is way to fast for you. According to your activity your fastest 1 min time was 4:33 min/km which is slower than 14 km/h
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@MartinZ and if you think 44 is correct and you desperately want to have the watch show this exact value, then just lower the value of your upper Zone 4/lower Zone 5 until the watch shows you 44, as said before. Then your anaerobic threshold HR is messed up, but that’s how the algorithm works.
