Badger6

The question really is: "What is the proper way to determine the LTHR to establish the 5 zones?" Short answer, do an FTP test with a HRM...and hopefully with a head unit (Garmin does this, not sure about Wahoo) that will calculate the value for you...it is not perfect, as in like doing it in a lab where blood is being drawn and tested, but it seems to be pretty close.

For years I used the %HR Max method, but it seems that I was always in Z3 or Z4, but my exertion was nowhere near that. Then I got a Power Meter, and I stopped paying attention to HR, other than as a secondary, e.g., was it climbing at a given power indicating that I was decoupling and becoming exhausted, but still my HR was higher than other persons I deemed to be similarly fit to me. Then I found out about the Coggan method of calculating HR...and, well, since I had a Power Meter and knew how to do an FTP test, and I had a HRM, and a Garmin that would estimate both the FTP and Lactic Threshold Values, I gave it a shot, and recalculated. Lo and behold, my zones expanded, and moved upward, significantly, and not my HR Zones seems to match my perceived exertion, and while I still only use the HR as a secondary metric, it is far more reliable, and actually tells me by Zone when I am entering into an exhausted state....and, when I need to rest, recover, etc.