# Thread: How come Friel and Coggan vary so widely on 'Zone 2'?

1. ## How come Friel and Coggan vary so widely on 'Zone 2'?

Example - LTHR = 172

Coggan Z2= 118-143

Friel Z2 = 141 - 152

I'm going to say that Coggan's method appears to be more of a 'Baseline' where Friel's seems to actually fluctuate in line with your LTHR.

For me 130 HR is NOT zone 2.5 ... 146... yeah... that seems legit. Funny that they both seem to agree on the top of zone 3 (Coggan 162, Friel 160)...

Thoughts? There is a big difference between 130 and 150!

2. If you are taking HR serious enough to where 5-10bpm worry you, you need a power meter. 5-10bpm can be affected by a great deal of things, and your HR can fluctuate that much between each ride just because of fatigue, weather, hydration, etc.

It's just a guideline. Take it as such, don't take it as a end of a cliff at the end of the zone.

3. Originally Posted by Creatre
If you are taking HR serious enough to where 5-10bpm worry you, you need a power meter. 5-10bpm can be affected by a great deal of things, and your HR can fluctuate that much between each ride just because of fatigue, weather, hydration, etc.

It's just a guideline. Take it as such, don't take it as a end of a cliff at the end of the zone.
this

effort that may be 150 bpm one day may be 140 bpm at the end of a training block

4. Originally Posted by GeoNLR
Example - LTHR = 172

Coggan Z2= 118-143

Friel Z2 = 141 - 152

I'm going to say that Coggan's method appears to be more of a 'Baseline' where Friel's seems to actually fluctuate in line with your LTHR.

For me 130 HR is NOT zone 2.5 ... 146... yeah... that seems legit. Funny that they both seem to agree on the top of zone 3 (Coggan 162, Friel 160)...

Thoughts? There is a big difference between 130 and 150!
You're probably better off googling for the answer, than asking here.

5. Cause Freil drinks his coffee before he rides and Coggan after.

6. I have one... and if you got the impression the '5-10bpm worry me' than you don't even want me to talk about power numbers! haha

7. hr is too variable, at least for me. if I rest/ride easy Thurs/Fri and do something hard Saturday, I will see 180s. Same hard effort on Sunday I will see 160s.

My threshold HR drops from around 182 to 167 after 1 250+TSS long day.

8. Originally Posted by GeoNLR
I have one... and if you got the impression the '5-10bpm worry me' than you don't even want me to talk about power numbers! haha
Sounds like you're answering your own question, in that case (with a side of hand-wringing). I learned quickly that HR was way too variable to use as a strict training metric.

9. just ride between 141 bpm and 143 bpm and you're all set

10. It's not only how zones (or levels) are defined, but how they're used.

11. When I'm riding and my ipod starts playing "***** Cat" by Elton John, my HR jumps 10 beats.

12. Originally Posted by jbroadway
When I'm riding and my ipod starts playing "***** Cat" by Elton John, my HR jumps 10 beats.
Really?

13. My HR is a pretty good indicator of where I am fitness wise, but then again, I am old.

14. HR is good once you've had some experience with it, but for me anyway it's only really useful to indicate how tired I feel vs where to pace an effort. I already know where threshold and the other zones are, based on RPE.

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