FTP Guided Test too hard, FTP not detected

Definitely don’t do it after a day at work. Your head will not be in it and desire to give up way too high. Rest day on a Friday. Get up an hour early on a Saturday with nothing else on. Decent breakfast. Wait 90min. Do test. Shower. Done

Thanks, but you missed the point of my question. This failure had nothing to do with my head. The test procedure seems to have changed from the last time I used it. I was asking if anyone knows what's going on there?

I never used FTP guided tests with my Garmin devices, but to me this protocol made no sense at all. Let’s assume that your properly measured FTP would be still 220 watt. Being able to ride in the range of 210-230 watt  for 60 minutes or so can be quite different from that to ride above 260 watts or so for 10, or even just for 5 minutes. You use your body differently. 

And generally saying, even if one does not want to make a real FTP test lasting for 60 minutes, the protocol should be much flatter in terms of power values.

This sort of step up (ramp up) tests may be good for LTHR and VO2max, but definitely not to measure something which definition is about “one can ride at X for an hour or so”, even if X is an average and not fully flat (constant) for 60 minutes.

nradov said:

Yes, I am aware that I can use other FTP test protocols besides the one built into my watch. I would like to be able to use this one for consistent results.

I do propose you forgetting this test or other similar built-in tests heavily ramping up, and if you can, just use a climb being long enough to ride on it for at least 20-30 minutes, preferably for 50-60 minutes. If you cannot then try to use the built-in test which first helps you to find your sweet spot (real range) then makes you ride in that range at least for 20 minutes.

And yes, I am sorry, but I do not know what exactly changed in the protocol, but if the old protocol was still about stepping up and up then my words are maintained.

Maybe the inventor of this test protocol you cited should have been thinking for a while about the different anaerobic capacity of the individuals.

Do you use Uwift?

Zwift offers multiple ftp tests, like a ramp test which is similar to the Garmin one.

No, never used Zwift. A lomg time ago I bought (2011 ???)   a non-smart Tacx Bushido and used for a while, but never tested my FTP indoors.

And having followed the evolvement of FTP tests, it is quite obvious to me that the tendency was to offer something faster and more comfortable (if possible) then the original 1 hour test.

And although you can read this sort of pure truth:

“Since by definition the best measure of performance is performance itself, the most direct estimate of your sustainable (threshold) power will be obtained by simply doing a time trial of an hour or so.”,  

the 20 minutes ttest was also spread widely, after FTP was created: 

“Realising the many challenges associated with this, (most notably the unpleasantness associated with a 1 hour max effort), Coggan and Allen devised a 20 minute test whereby a subsequent calculation could be made using the average power for the 20 mins to establish your estimated FTP for 1 hour.”.

And even this “second best” protocol, I mean 95%* avg power over 20 min steady state all-out, can have a substantial distortion.

Check

“Many coaches and athletes define functional threshold power (FTP) as 95% of the average power from a 20-minute, steady-state, all-out time trial. While this may provide an accurate FTP for about 50 to 60 percent of the population, it doesn’t hold true for a large number of athletes. Among the cyclists I coach, the range of FTP relative to 20-minute power is as low as 86% for a track sprinter and as high as 96% for some time trialists.”

So my conclusion is: if you shorten and shorten the timeframe  of thes test and/or you go away further and further from steady state power exertion you create more and more uncertainty regarding the accuracy of your estimation.

So what is proved by the fact that also Zwift has ramp tests (sorry I had thought it was called ramp up tests, fyki I am not a native English speaker) ?

It proves that we live in a consumer world where the good feeling of consumers tend to override the scientific approaches. :-)

I answered the original poster...

Ramp test should be a accurate enough for hobby cyclists and to dial in the FTP based workouts.

No, I tried Zwift but didn't like it. I am fortunate enough to live in a place where we can ride outside most days, so I only use the smart trainer occasionally for workouts where I want to hit specific power targets.

I did a test end of February on my Descent Mk2i (so after I got the 24.00 update). For me it went the opposite way. I had done an FTP test a year earlier where it detected 270W as FTP. In that it was 265W for 4 min, then 295 for 4 min and 320 for 4 min. Felt like I was almost dying at the end and cadence kept dropping. I'm a stronger cyclist in general now, so was interested to see what I would get. Test went 245W for 4 min, 270W for 4 min, 300W for 4 min. I felt pretty fresh during the 300W and ready for more, cadence was pretty stable, but then it just stopped and gave me an FTP of 265W.

In retrospect I realize that I shouldn't have tried squeezing it in during lunch. I ate during the warm up phase and then my heart rate was all over the place during the ramp test. On the previous test there was a nice slow steady increase of heart rate during the ramp up, which is likely something that the algorithm wants for its analysis. 

So my guess is that the test hasn't changed, but it's likely very sensitive to how your heart rate behaves when you do the test. 

The heart rate chart shows a fairly steady increase during the ramp up phase through the end of the 265W step. At that point I hit 188bpm which is close to my max for cycling, but then the test kept going to a 285W step and I couldn't keep up. 

The previous test shows a similar steady increase in heart rate during the ramp up phase through the end of the 265W step. At that point I hit 179bpm and the test automatically stopped. I was in a little better shape for cycling then (have been running more than cycling lately).

What I'm trying to understand is why this latest test kept going even though my heart rate was so high? It seems like the test has changed.

In my case the heart rate was just barely touching the low end of my configured zone 5 when the test stopped, lower than it was in the previous test. So it doesn't automatically push harder now than it did before.

I don't have any deeper insights. It's probably detecting something with the heart rate increase or HRV when it's trying to decide how fresh you are. Maybe it thinks your running fitness better translates to cycling? The performance condition is improving during your test, so the watch seems to think you're doing better and better? On your previous test the performance condition slowly declines during the test. I've found that specific metric to be fairly dodgy on my rides..