"Your threshold HR has increased by 6 to 180 bpm from 98% of 20m at 184 bpm" .... AND NOW?

I am coming out of a Zwift race, where I did a 33 min max effort and my HR was obviously high for reasonably long time.
Intervals.icu was very smart in sending me the following via mail:

  • Your threshold HR has increased by 6 to 180 bpm from 98% of 20m at 184 bpm

My challenge is that I am not smart enough to know what to do with it!
184 is not my MAX HR. Last summer (35 degrees, riding outside in the sun and hitting a hard hill) i did more that 190.
BUT apparently the threshold is materially different (+6 vs current setup)

Net: what is recommended to update?


There are certainly more knowledgable people around here but I would suggest to update both.
As far as I know Max HR is just that, it’s the maximum your heart can go and it is not dependable on external factors. That doesn’t mean that you will always be able to reach that maximum, but it is relatively stable in trained people. There is some decrease with age. I ussualy decrease mine about 5bpm when starting a new season and then let it update during the season. But be sure to not accept Max HR from a measuring artifact! Mine has been stable at 185 for the last four seasons.
Treshold HR is more variable because it is influenced by your training. A higher THR usualy means better fittness. It is influenced by external conditions like heat and hydration. If you reached the new THR in “normal” conditions, I would accept and update.

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You can click that message and enter 180 in the LTHR box and click calculate to set new HR zones. As @MedTechCD said don’t change your max HR (bottom right hand corner of grid).

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thanks. I will update the threshold, but keep not select the option to recalculate past sessions.
+6 is very likely a combination of (a) lockdown zwift riding and (b) not trying hard enough in the last months [doing intervals never longer than 8min … ]


I guess I’m doing it wrong, when I click the message I don’t see any way to change the LTHR or recalculate. Perhaps I’m not clicking the right message?

Oops. I broke it. It’s fixed now. Tx for the report.

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In FTP don´t work, is broke like Threshold

@Alessandro_Marvaldi have read here; it will explain the threshold HR.