That sounds like a great idea to me! I am not a very experienced rider, but have just within the last months started to do the training plans and have become more interested in power and heart rate.
Would that work like the automatic FTP rating that you get from Zwift? Which is to say that Zwift would have your heart rate data from your rides and then your maximum heart rate would be calculated based on previous sprint or climbing efforts? And then the box in the upper corner of the screen could light up with the color of the heart rate zone you are in? Sort of like where you have the colored power-zone readout along the bottom of the screen during workouts, or which is accessible in free rides from the companion app dashboard by clicking the blue button at the bottom that looks a bit like a graph, or by clicking the G key on your keyboard.
I up-voted this and will be interested to see how others respond.
No need for this myself but also voted - however, suggest you also vote up HUD customisation thread which covers a multitude of requests including AVG watts and HR
Emiel, I read a stack of books on cycling training from several popular coaches and learned that calculation of HR zones from max heart rate is very inaccurate. The reason for this is that because max heart rate is very difficult to determine. One has to truly push oneself to the limit. This is very difficult to do, and can be quite risky for people who are no longer young, for those who are poorly trained, or have health conditions. Instead, it is recommended to either rely exclusively on power (perhaps using heart rate as a complementary parameter), or build HR tables based on lactate threshold heart rate. Without lab equipment to determine lactate threshold, one can use FTP, and this becomes more or less your heart rate in steady state when you ride at your FTP. In any case, HR may drift quite a bit depending on ambient temperature, on how tired you are, etc., etc. The bottom line, HR zones are not that straightforward and have a limited usability, according to many coaches.