Usefulness of cTHR value


I rode my mid-plan Half Monty test this morning.
I got an interesting increase of my MAP and FTP values.
On the other hand my cTHR value has decreased from 179bpm to 167bpm.
That does not worry me because I think previous value was overstated. I made the Full frontal was made less than 2 days before my third anti-Covid vax, and I was feeling that my heart rate was abnormally high, reaching a max value never seen before.
In fact I was just asking myself the importance of cTHR, as I’m following a plan and riding all the workouts on my Kickr ?
Are the workouts adapted with this cTHR in any way ?

As far as I know the only thing that changes are the boundry values for your heart rate zones. I don’t think anything actually changes in the workouts themselves.

If you haven’t seen it already, this short explanation is useful:

I tend to find my cTHR changes by one or two either way on Half Monty. 12bpm is a big change but at least you have an explanation.


I find knowing my cTHR very helpful on outdoor endurance rides for pacing as opposed to power which fluctuates too much. Indoor, it helps me reset my perceived effort when I’m feeling ready to bail but my HR says I’ve not even begun to suffer yet.


I find the cTHR rather useless.

I have to admit, I have not done many HMs and FFs to get decent statistics. But the last few tests (in chronological order) gave me a cTHR of 156, 179, 161 and 168. As long as it’s all over the shop like this, I cannot do much with it.

Personally, I’m blaming asthma: the strength is there, but the oxygen is sometimes completely lacking, blowing up my cardio system in the process or not managing to kick start it at all. I’ll stick to the 4DP numbers for training. On the road ( I ride alone ) I just ride what feels right at the time.

Like @Sir_Brian_M to estimate my effort and how much room I have left in my tank. At the same time, my HR is relatively consistent/stable throughout my activities - I know if I hit a certain value I will only have that much time left to stay at that effort before I will need to back down (especially at efforts close to the upper limit).

What I wanted to add is that breathing exercises helped me a lot with having some control over HR. Some good tips about this you can find by doing the Primers workout. There is very good information there about how to breathe. (I took that and research it to a higher level because of other personal interest / health problems.)

Overall, for me this parameter is very useful and so far the estimates I get from the either test are pretty valid.


You mean Tapers I think?

Sorry, Tapers is the right workout. My bad.

cTHR is really useful for me when racing. I don’t have a power meter on the TT, MTB, or CX, so for races that are around an hour then cTHR is a threshold heart rate that I shouldn’t go over - if I do then I go pop.

FF is a really good indicator of cTHR, HM not so much.

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To add some more informations: I’ve plugged to my Strava account, and it has analyzed all my activities. On the period between my FF and the HM this morning it says that my threshold HR is 170bpm. I don’t know how it calculate that, and if it’s reliable.
I’m gonna keep an eye to this indicator.

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Is there a cross walk of cTHR and power? Example would be if my Zone 3 cTHR (Tempo) is X than I should also be trying to main a range of watts between Y & Z OR is there too much fluctuation between the two have a meaningful set of comparisions.