Inscyd test vs WKO? Polarizd vs ... SST/FTP?

Hi guys,

Just finished my INSCYD test. A 20sec test. 3min (367W), 6min (329W), 10min (319W). The report was a little bit confusing. Vlamax was 0.48 (ok because i am a fondo rider mostly). Fatmax was 166 (seems low?). But my AT was set at 253w (78.5% vo2max).
This seems strange to me. Because in WKO, my mFTP is 275W (and mostly the last years i think my ftp was between 270-285). I did some good base training this winter, with some sweet spot work, base miles on zwift and sometimes a zwift race. Last month I did 1x60min 251W (SST) at 156bpm. And normally when I go towards 270-280 my hearth rate goes to 165.

They suggest doing some polarized training to increase my vo2max. Before the INSCYD test I was looking to do a more SST/FTP plan. So a little confuses what to choose? Certainly after the 10min test, I think I can do a FTP test (20min or Kolie Moore protocol) that would suggest an FTP above 275. But what about the 253 from INSCYD? It was just power based (ppd) no lactate.

Any thoughts?

I’d discuss this with the coach that processed your Inscyd test. My understanding is that if you have a well tested FTP, you can enter that in Inscyd rather than let it extrapolate from the shorter efforts.

Personally, I’ve been trying to determine if Inscyd really gives one much more than WKO5. It may be easier to implement and give the athlete a nice report.

@stino77 if you’re interested you could send me the missing data (20s Watt, body fat and weight) and I can run it through my implementation of the metabolic simulation algorithms.

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I think that’s your answer right there.

Meaning that fond riders should not do an Inscyd test? :wink:

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That was the initial idea do to the test once. But 253W vs 275W (and i think after the kolie moore ftp test it will be higher) is significant. Or should I consider those numbers otherwise? 253W AT vs FTP? (but thats the same, not?)

Also mFTP is 274W with TTE 48.

What’s the range for AT in Inscyd? Is the 253W the middle of that range? Is that why you’re calling it your FTP? (I’ve had two inscyd tests, so I’m familiar with the report)

To answer your questions. In terms of power numbers (zones, etc.), Inscyd testing did not give me more than WKO in trained hands. It was easier to understand (since I was self-coached at the time), and I liked being introduced to the idea of getting away from a single number.

I’m going to stay out of the fuel utilization debate that has occurred elsewhere (because I’m simply not qualified), but when I got my Incsyd tests I definitely appreciated and used the carb/fat utilization estimates. Not sure if there is a chart for that in WKO. So that’s something if you trust the model.

My FTP and middle of range AT in INSCYD differed but not significantly. However, I’m not someone who ever had vastly different estimates with all the different types of tests (KM baseline w/ TTE, 20min 95% w/ blowout, even 8-min ages ago, 75% of MAP, even though it could be 72-77%, and INSCYD all gave me similar figure…I’m TTer phenotype)

My experience is similar, INSCYD test gave me an AT which was almost 30W lower than WKO & Moore Test. Basically all values came lower than expected and the threshold I got is my tempo pace. I think it’s partly because I didn’t do quite 100% in all of the tests which is fixed in the times when doing it in Zwift vs outdoors where you have a range. But also the claim was that the AT from INSCYD is somehow more physical than the “typical” FTP numbers (what ever that means…) and often lower.
So my conclusion and also their recommendation is to repeat the test, possibly outside and trying to achieve 101%. Otherwise it seems to underestimate quite a lot for me.

I did the test outdoors, because I know outdoors I can push more watts then indoor. Al intervals done on the same route (flat headwind and avg pwr almost same as np). And it was all-out, maybe the 3min I can push little more but my feeling, the test was ok. Your physical vs typical makes sense. What number did you choose for your zones?

Numbers (plural). It’s a range. I realize software (zwift, TR, etc) force you to enter a single number, but you don’t have to ride that way (or more importantly, think that way). Split the difference, see how you feel during workouts close to threshold (SST, etc.) and don’t get in your head about it.

Range is 235-270 so it is in the middle. As far a I know, the last years always have an FTP between 270-285. And looking at data of fondo’s, races, that seems in the correct ballpark. I did 251W a month ago as a sweetspot 1x60min session, that was though but it was not all out. So that is why the 253W as an FTP (or AT) number from a test seems little strange.

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Ok. Cool.

Fresh = upper part of range.
A bit cooked = lower part.

Also TTer phenotype, that is why I think the difference is strange. I think I will complete an FTP test soon and then I can see what my numbers suggest again towards the INSCYD test.

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I would just do KM baseline w/ TTE. One thing that I understand the reason for (proprietary) but find a little bit annoying is that we don’t really know (unless someone has discussed on forum somewhere) if that middle of AT number is “hour power”, estimate of LT2, or an actual attempt at FTP (using one of the current protocols). I did a 20min all out over-paced effort as part of my Insyd test so I’m pretty sure mine was just 95% (which explain why it’s the same as my…:slight_smile: 95% 20min ) :slight_smile:

Seems like that would explain the discrepancy as hour power is typically lower than FTP and LT2 almost certainly is lower. (associating a TTE w/ FTP is still a fairly new concept and likely not a thing in Inscyd).

Definitely strange. Agree.

Edit: and sorry to beat a dead horse on this one, I’ll stop after this, but it’s critical to treat it as a range, not a number, regardless of how you determine it.

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+1 on that. You are right. But with that number they adviced me to go for a polarized training block. And I was planning something completely different :slight_smile:

I just keep using the WKO5 iLevels atm. I’m doing kinda polarised anyway so it doesn’t matter that much right now. Maybe more interesting from the results was the carb and fat usages.
I’ll see what I get from it next time…

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Agree. Here is what I found… INSCYD AT is a pretty big range, my first test was 234-269W with a target of 252 and my own long field test (52 minutes) put it at 245 and WKO had mFTP of 242.

So @stino77 I would recommend treating AT like a range, and not a precise number. At 250W my power meter’s +/- 2% accuracy means +/- 5W. And then you have daily fluctuations because your body is not a robot. In my own mind I think of FTP as a 10W range. Of course for metrics like CTL and TSS you need to pick a single number.