@Gurbe_Willebrords I’m going to just re-hash what the TR ramp test is (which you know, but just for the sake of completeness) mention a couple of papers supporting the notion the among weekend warriors and highly trained cyclists there is significant population of athletes that will find the TR Ramp model unusable…and then copy & paste some text re: TR ramp test that I’ve posted before (pay close attention to the example rider in that text)
TR ramp test is a Maximum Aerobic Power (MAP) Test. MAP tests are an age old way to estimate VO2max. TR FTP is an estimate of FTP based on the estimate of your VO2max (MAP). So an estimate of an estimate. FTP as a percentage of MAP can vary substantially from rider to rider. Way, way back in the day Gollnick did a study on enzyme effects of cycling training…subjects in the study did a ramp assessment & then cycled at 75% of their ramp assessed VO2max 4 times a week for 5 months. Here is what Gollnick observed at the beginning of that process:
“Initially subjects could not tolerate this load for the full hour and it was reduced to about 65% of VO2max during a portion of the exercise bout…At the end of the training program most of the subjects were working for 1hr at 85% to 90% of their VO2max”
If you go read that paper pay special attention to Table 1, 2nd subject. PD Gollnick’s paper…subject PDG. Hmmm. Not just an egghead observer.
Also way back in the day, Coyle/Coggan looked at 14 cyclists with mid-60’s VO2max numbers & a lot of cycling experience. They did a ramp test to establish VO2max and took lactate curves to establish Lactate Threshold. Among those well-trained cyclists LT expressed as a percent of VO2max ranged from 59% to 85%. Mean LT/VO2max was in fact 74%. But standard deviation was over 9%!! Even among well-trained cyclists, out of 14 cyclists, only one of them would have been well-served by a 75% estimate. The rest would have been either overtraining or undertraining. If you read this study pay special attention to Table 1.
PD Gollnick Effect of training on enzyme activity and fiber composition of human skeletal muscle.
Coyle/Coggan Determinants of endurance in well-trained cyclists
Here is what I’ve said about the TR Ramp Test in the past:
"I suspect correlation between TR MAP-based FTP estimate and actual FTP or actual hour performance is not that great. For a few reasons:
1.) TR is pretty honest with their user base. They never talk about this. We talk about it a bunch. What does that tell you?
2.) A progressive ramp test is designed to estimate Maximum Aerobic Power, or MAP. Pegging FTP at 75% of MAP is using an estimate to make an estimate. Usually such things don’t have good R^2. 
3.) There is a lot of data from other sources suggesting that individual variation from the 75% rule can be substantial. Anecdotally, I think dialogue on this forum only serve to support this notion.
MAP-based FTP is a tool. It designed primarily to improve testing compliance & I think it’s good for that. Directionally, it’s a good measure of what’s going on with FTP. On an absolute basis, it can certainly OVER report FTP and UNDER report FTP. Individual users should be aware of where they sit on that continuum and either adjust plans accordingly or take steps to correct deficiencies (see my hour of power threads for more thoughts on those steps)."
" Here is what I think is going on: TR uses (primarily) a MAP ramp test to determine FTP. Most would perceive all TR plans to be FTP based but they are not. They are Maximum Aerobic Power based & the first thing you do with your Maximum Aerobic Power is multiply it by 0.75 to get your ‘FTP’. So, really, all training plans are based on 0.75*MAP…not FTP.
Here is the problem with that MAP-derived FTP number: if you compare the actual FTP to the actual MAP of a population of riders with similar MAP you get a BROAD distribution. Remember that paper from way back in the day by Coyle and Coggan where they did exactly that? Determined FTP as a percentage of VO2Max for a bunch of trained cyclists? Some of them were 60% & some of them were 85%. A lot of them were less than 75%.
TR has no way to deal with those riders who have sub ~70% FTP. And in fact, at least for the sustained power build plan, TR puts those riders into a destructive positive-feedback loop. Imagine our trained cyclist who has an FTP that is 60% of their VO2Max. TR uses a ramp test to estimate VO2max, then assigns an estimated FTP of 75%*VO2Max.
Yikes! Our 60% rider’s next workout is Avalanche Spire! The poor fellow is doing over/unders at (nominally) ~118% of his true FTP. That’s a VO2Max workout . So he slogs it out. Does what he can. It’s a super tough workout…maybe he can’t complete it all. People on the forum tell him it should be ‘hard but doable’. Especially those riders who are lucky enough to be in the >80% FTP-to-VO2Max club.
Our 60% rider is one tough cookie. He hammers through workouts as best he can. Then, when it comes time to do the next ramp test, guess what? He hasn’t been doing sustained power for the past few weeks AT ALL. He’s been doing a ton of VO2max work. Guess what that does to your Maximum Aerobic Power? It makes it better…so now his next ramp test…surprise, surprise…is a little bit better.
But his FTP probably hasn’t improved that much.
That’s what I think was going on with me. My physiologic profile favored Maximum Aerobic Power. As a result my MAP test results caused 75% of MAP to overestimate my FTP. So when I executed a TR workout at 95% of TR-ramp-test-derived FTP…I as really doing intervals at >110% of true FTP."