Yes I “force fit” Friel’s 7 zones into the Garmin 5 zones, its the right-hand column:
Its ugly hack, but much better than the 50/60/70/80/90% default zones. And then I usually ignore looking at HR in Garmin Connect.
What about as a suggestion, if HR is in z3, ride to HR. If in Z1, ride to power
What if your HR is in zone 1 during a zone 2 ride simply because you’re tired? Wouldn’t riding to power just cause you to dig yourself into an even deeper hole?
Most likely not, those are Friel zones and should be based on LTHR. And even if LTHR is accurate, Coggan and Friel zone2 HR are different:
Zone2 HR:
My guess is that you would have better zone alignment if using Coggan HR zones.
Simple reality is that power and HR zones don’t always align.
Cool info. I don’t honestly look that deep into HR any more. It check it on occasion to look for things like new max in a season, and decoupling, but I seldom sweat the details.
Was just curious what David thought since his is so well aligned and mine is clearly not. Won’t make a difference in my training or use, but interesting anyway.
I believe David is using Friel HR zones in intervals.
Also perhaps I’m a bit confused - the “Combined Time in Power & Heartrate Zones” often confuses me and I don’t use intervals.icu. Believe that chart uses only power data if all rides have power data, and for any rides without power, uses heart rate. Or is it really combining all power and all HR into a single chart? 
Can’t say I know those details, but all my rides include power and HR except my MTB rides (which are quite rare overall).
While my earlier statements hold true about alignment of power-only zones and HR-only zones, I’m not sure how to interpret the Combined chart (left side) in your screenshot.
@mcneese.chad your power-only zones are basically the same as your combined, given you mostly ride with power. And back to my guess, you would probably see better alignment using Coggan HR zones. Personally I’d file Power/HR zone mis-alignment under ‘might be more aligned with Coggan zones - whatever - nothing to see here.’
I don’t think I saw it mentioned yet here, but are you seeing your heart rate drift into Z3 after a long period of time? This is normal and called cardiac drift. Google aerobic coupling, and you’ll likely find some Joe Friel articles on it.
Yes it favours power over HR but will use HR time in zones if power not available.
I don’t know actually. It would only matter if you were training to HR zones instead of power zones some of the time. I do that sometimes on the MTB.
Neither. Follow RPE. Listen to your legs & your body. Slowly warm up, then go at a pace that feels like you could hold it for 5 hours or more, irrespective of how long you’re actually planning on riding for (5h is totally arbitrary and more of an example of a “long time”). If you’re unsure, err on the side of caution, at least at first. Holding 60% vs 65% FTP for 2 hours for example, is unlikely to have a significant difference in adaptive-stimulus for that ride, but constantly pushing for a handful of extra watts could have a significant difference in terms of recovery required in the longer term.
Copy that. I almost never drive by HR. Just power and RPE, so sounds like nothing to sweat. Thanks for the look. 
After the post of @bbarrera i realized that the Coggan heartrate zones dont fit for me. For many years i have problems to hold my heartrate in Z2 when iam going to the middle of Z2 powerzone. Even when my heartrate is going into Z3 in een groupride i can still do a conversation and can hold that heartrate for hours. My LTHR is 183 (I did Joe Friel test, and test in lab) with max 198.
Now iam looking at Joe Friel zones and it fit a way better. For example, a normall endurance iam really fast at HR 150 (83% LTHR). In Coggan zones is that the high end of Z2. Friel is from 146-163.
I have changed a few little things based on my own expersions, but realize that every zone has not a hard switch like a light switch on/of:
Recovery: when iam riding at hr 146 i can breath trough my nose, for me is that a recovery pace.
Z2: above hr 160 iam feeling more into tempo, but hr depens on the day and time in the season.
Tempo: tempo feel simular like the Joe Friel standard tempo zone.
Sweetspot: i called subtreshold sweetspot, so it is in line with my powerzones.
FTP: my FTP is hr 183. So i think between 179-187 iam into FTP, but think also that 187 is allready VO2max (not a light switch).
Vo2max: 187/188 and higher…
I dont have make zones for Anaerobic capacity because i think above FTP heartrate is not a good measurement due the delay and short efforts. It is all out…
The variability between individuals is kind of crazy, your zone 2 would be my threshold. LTHR for me is 161, 5 or 6 years ago it was 155🤷♂️.
Yes compare to each other make no sense…
I can ride a race for 1.5h with avg heartrate 175.
When i was a junior cyclist (15 years old) my max heartrate was 216
