I am doing the climb interval training and I noticed two things yesterday.
I did not go into the ‘red’ like I used to. somehow I can’t or won’t go above 185 as previous I maxed out at 192 -193 quite quickly. now it takes longer to get in the higher heart rates, but also it feels like a ‘governor’ or limiter is on my heart rate.
along the lines I find that the ‘zing’ is out of my climbing. I can go longer both sitting and standing in my perception, but not as quick in the acceleration. like my body tells me not to go in the red.
before you state the obvious, I asked my wife if I have gotten smarter over the years and in particular the last months since I am doing a training plan, and the answer was NO.
So a lot of things impact HR, and I mean A LOT! So it is hard to say what exactly the reason for that is. However I will note that as you become fitter, you can hold a higher power at a lower heart rate (which is why it’s important to have your zones set correctly). Thus, if you skipped the FTP test (or didn’t go hard enough during it) that could be the case. Another reason could be if you are riding at a higher elevation when doing these workouts.
For the zing - this could be due to not getting enough rest/too high of a training volume (fresher is faster ) or simply the fact that you are now focusing your training on sustained efforts with the climbing plan.
That plan is designed to prepare you for longer efforts like you will see in marathons, stages races, and fondo type events… not for short efforts like you need if you were doing events such as crit racing.