I’m delving in to the training zones for outside rides, I know TR does all of the figuring for us on its workouts but I just want to understand something a little better.
My LTHR is 176bpm, and my FTP is 273W.
According to Coggan, Zone 2 for me is..
Heart rate - 69-83% LTHR, which means mine would be 121-147BPM
Power - 56-75% FTP, which means for me mine would be 153-207W
I dual record the TR workouts on my Garmin and use the Garmin on its own for unstructured zone 2 rides
What I’m surprised to see is that Garmin reports the HR zone as expected (121-147BPM), but even though I have zone 2 set correctly as 56-75% FTP on the edge 1040, the output on the FIT file shows zone 2 as 55-74% FTP (150-205W).
I guess it’s just a difference in the way Garmin handles the numbers, but what do we think Coggan actually intended it to be? It bugs me a little bit that Garmin handles the HR and power start/finish percentages differently.
This is truly the ultimate of hair-splitting, but the source document here is Training and Racing with a Power Meter and Z2 is defined there as 56-75% of FTP. The heart rate averages given are “guidelines”, they are not intended to be training zones. In other words, when riding endurance you should see HR between 69-83% of threshold HR.
The Zen master way is RPE 2-3.
Ultimately, if you’re doing it right, you’re not riding right at the top end boundary anyway on a true endurance ride. You should always see some time in Z1, Z2 and Z3 of a proper outside endurance ride, something like 10% - 85% - 5% is pretty good in terms of TiZ.
Such small variations don’t matter, the hard zone boundaries just come from the fact that you will need to introduce them when you do numerical analysis. And HR zones is yet another can of worms since heart rate is impacted by many other factors.
In practice, if you think about Z2 training, you would probably want to split Z2 until upper and lower Z2. 55–62ish % FTP are very mellow and relaxed. Whereas averaging 65–75 % FTP (or having an intensity factor in that region) places more strain on you in my experience.
