I’m back to my Polar Vantage V2 watch for a while, because I like its look and lightness, plus I appreciate a lot the sleep analysis. I also use Stryd footpod during my runs, I started using Stryd in 2017 for distance and pace accuracy, but also appreciate the running power and Polar plays nice with Stryd. I must admit, since I’m not living (and running) in a hilly area, I could live with pace based training .. but running power is a very good option for me as a data geek.
Anyway … the reason for this post is that in the last 10 days I run three times in an awkward situation, when the structured workout based on power was unusable because Polar stubbornly was reverting the MAP value (https://support.polar.com/en/running-power) to the Polar running power value, overwriting the value I captured manually from Stryd.
When using the default power zones, any change for the MAP (Critical Power) is also changing the zones, therefore the running in Zone 1-2 in the structured workout become impossible, since the values were way too high.
Sure, that’s fixable .. it takes just some minutes to change the MAP value again and sync your watch with Flow mobile, but the first time it also takes some time to debug and that’s not always funny with it’s -5 degrees Celsius.
Now, I changed the power zones to custom – that will require some more work when the MAP/CP values changes .. but at least I hope that I won’t be needing to stop my workout to reset the MAP and sync the watch after a false start of the workout.
I tried to understand what’s causing this issue…some days was just working fine and then suddenly I saw the change again when starting the workout – I still don’t have a clear pattern, the only thing that I’ve done is adding some new sensor (like an Polar H10 or Verity Sense) since the previous session…I don’t understand how that would affect the definition of the running sport profile for Vantage V2, but who knows..
So, just in case you experience the same issue, change the power zone type to custom to avoid this annoying start of your power based workout.
Lately, I become more aware that it’s only a significant minority of users who are interested in running power, even less interested by structured workouts and combining that with the profile of the Polar users, you’ll find a even smaller audience – anyway, I hope my experiences will help you to avoid some awkward moments in your training.
Stay well and enjoy running!
Liviu Nastasa 
Hi, what do you think about the power measurements from the polar vantage v2 against the Stryd? Are they comparable and reliable? The reason I also ask this is because I would like to buy the book “the power to run” but they use Stryd and it would not be great if I buy it and I can’t use it. Thank you.
Today, there are several devices (Polar, Coros, Garmin, Stryd, Apple Watch) that capture running power and none is considered “the standard” even though Stryd is the “oldest”. In my experience Polar running power and Stryd have similar behaviour in field, the value from Polar being always higher that Stryd so you may enjoy the benefits of using running power if you use Polar without any other accessory.
Keep in mind the fact that any watch that tries to measure running power without a footpod, will use the GPS (and accelerometer, gyroscope) as a source of information for their math, and the result will depend on the accuracy of the GPS – so there might be some limitations.
There is nothing bad in using “The power to run” for understanding the concepts of running with power (they will apply some of them to Polar as well), but you’ll miss some of the information Stryd exposes just by using the Polar alone, since Polar Flow doesn’t display the power curve or something similar, also doesn’t have any of the running dynamics measurements collected or displayed.
For a more detailed comparison of running power on different devices you can have a look here – https://www.dcrainmaker.com/2022/06/running-power-comparison-garmin-stryd-polar-coros.html.
Briefly, if I wouldn’t have my Stryd and I wouldn’t buy another (for distance measurement), I’d use the running power from my Vantage V2 as a reference for my training, it’s better on hilly terrain than using just HR or pace. The relevant values for zones will be kept updated when you perform the running test regularly and things should be fine.
Thank you very much for the answer.
I found that if I delete my MAP value it turns blue (estimated value). Then I can select custom power zones and set the zones where I like and they don’t reset. For some reason if you have custom zones selected AND a MAP value set, Polar Flow can’t seem to figure out which one to prioritize.
I also find the MAP is a more nebulous value to work with anyway. I just manually set the zones to match the Stryd zones depending on my CP that month. When the CP changes, I log back in, reset my zone thresholds and save… takes a few minutes at most.