Hello Pia,
I am not familiar with this polar option. I am hesitant as the reason the HR monitors aren’t very accurate is due to the distance from the heart. This seems to be using very similar technology as the wrist HR monitors. I am sorry to hear the chest strap causes you so much pain and discomfort.
If you still have an old chest strap, I would recommend using it for your AeT Test. See how that feels. Once you have that data you will hopefully be able to use your wrist monitor to at least train in the same zone even if the watch is saying something different than your test. As long as you are consistent and you are training below AeT you shouldn’t need to wear your chest strap.
If you don’t have a chest strap, there are other options (not as accurate) but still useful to estimate where your Aerobic Threshold is without an AeT Test. We will talk about them on Tuesday 🙂
I hope that helps!
Maya