HR-zones compared to power after FTP/Ramp test

Hi There,

Just recently I started using TrainerRoad and had previously done a 20-min FTP-test (outside) before the Ramp test I did at the start of this week. The 20 min and Ramp test gave similar results (20 min = 368 - ramp test had to stop at 460) so FTP is around 340/350 watts. When I’m doing a Z2 ride, say at 220w either indoors or outdoors my HR ramps up quickly (in like 10 minutes from 120 to 140) to the upper end of then Z2 (145ish) and then stabilises somewhere in Z3 at around 150/155 bpm, using Coggan zones for HR.

My LTHR is 175 the question is, should I stick with Coggan zones and ease off on the Z2 rides and keep the HR in the 69/83% range of my LTHR. Use different HR zones, like Friel maybe? They seem to be more in line with my power zones when comparing the two or just leave the HR zones and focus on keeping sustained power and let the HR drift away.

I’ve looked into the different topics already started on this matter but in most topics it looks like the power zones are higher compared to the HR-zones, my case describes the exact opposite!

Thanks for the advice!