I know this has been covered in various ways before but I have run across something a little confusing. It has been a while since I have done a test week so did my bike today. My 20 min average was 251, which led Zwift to adjust my FTP to 138. However, Athlectica has set my critical power at 148. Is this correct?
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Typically, Critical Power is a bit higher than FTP. Plus the way Zwift and Athletica calculate the two are different as well. So Iād stick with the Athletica CP and go from there. Good test!
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Never seems to be the case for meš
Throughout the years, the FTP analysis of intervals.icu (based on different durations from 6ā¦30 min) as well as 0.95 * AP(20ā) always gave me higher values than any CP analysis (atheltica, i.icu, others).
For practical purposes I always used my FTP from the FTP analyses and the (higher, in turn) Wā from the CP analysis ā seems to serve me well for HIIT training and racing.
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Interesting, Joku!
This is a good read about Critical Power and the difference between CP and FTP.
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Well, I like the Highnorth website, too. But there is not much detailed info in this pageā¦
Anyway, I quickly put in some max-effort numbers for 5, 10, 20 min from the last weeks and let it calculate ā¦ The CP comes out as the same as intervals.icu and Athletica.ai. But the estimated FTP from that calculation is much lower (3.5 %) than 0.95 * AP(20 min) ā the 20 min valued I put itā¦
0.95 * AP(20 min) Is what I would assume to be my āclassicalā FTP at this time. Currently, this is very similar to CP and one could assume them to be the sameā¦ On the other the eFTP calculation of i.icu, e.g., using the āsingle max effort and 3-parameter Mortonā formalism, is ~3 % higher than CPā¦ Iāve to see which duration it takes as my max effort, could of course be a bit inflated from anaerobic contributions for a short durationā¦
I.icu and a.ai, of course, both have much more data (than three values picked from a short max-effort list) and could potentially use ābetterā max. efforts (5:35 min, etc.), which in turn could lead to higher CPs in the calculation.
Btw., I do use CP as āfunctional anaerobic threshold baseā for my workoutsā¦
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How do you get Athletica to update the zones?
Does it have to be a āPower Profileā activity?
Iām asking because so far Iāve only seen the higher zones (Z6/Z7) update after a hard acceleration, but the lower zones always stay the same, even after a good 5min effort.
Even more, CP value in āOverviewā tab doesnāt match the one under āCycling Power Profileā - both 6w and 3mo values.