Unable to finish Threshold but VO2 is Fine - Why?

Hi Guys,

Help a Noob out here. Generally with the new workout levels for each categorization it goes from more easier (Endurance) to harder (Anaerobic/Sprint). I find with Endurance it’s pretty easy to complete the workouts even at higher levels at the end of the spectrum , it’s just putting in the time to complete them. The anaerobic workouts are obviously more difficult and need more effort.

However, I notice a big discrepancy in my ability to finish the Threshold vs. V02 workouts. I can and have completed V02 workouts that are close to level 7. However for Threshold workouts I struggle to even complete 4.5 - mostly it’s the over/unders that destroy me. Heart rate and fatigue hits me hard by the 3rd set of over/under out 5 - usually resulting a failed workout. What does this usually mean, usually threshold and V02 are pretty close in terms of energy systems, no? And best way to build on this is focus more on threshold workouts I guess?

Any suggestions or advice would be great.

  1. Testing - if you find vo2 max easier than threshold and you test by the ramp test your FTP could be overestimated by the anaerobic contributions. So your O/U could be over overs. Try longer test - try holding power for 35-40 minutes as a start point. It should be a lot closer to your FTP. You will find a lot of info in different topics. And I recommend this topic for additional info about longer test:
    Kolie Moore's FTP test protocol - #443 by paulgrav

  2. What happens over FTP is highly individual. Ability to do vo2 max is not in relation to FTP. That is why doing vo2 max by the percentage of FTP is usually not very useful. It all depends where your FTP is in relation to pVO2 max and how your anaerobic capacity looks like.

  3. My personal experience with doing threshold and O/U is that doing longer Z2 rides helps a lot in terms of improving substrate utilisation and lactate clearing. With wrong FTP o/u can be not doable.
    A little bit more info in a older topic of mine:
    Threshold riding for beginners
    Maybe you will find something helpful there.


They say you can’t compare workout levels from one ‘zone’ to those in another zone.

Are Workout Levels comparable from one Zone to another?

No. Workout Levels are classified in two ways: (1) Zone (2) Workout Profile. An example of Zones would be Endurance, Tempo, Sweet Spot, Threshold, VO2 Max, Anaerobic, Sprint. Each Zone has various different Workout Profiles within it. Workout Profiles represent the interval structure of the workout. For example, the VO2 Max Zone has On-Offs, Float Sets, Sustained Intervals, Traditional, Attacks, and more.

Workout Levels within a specific Zone and Workout Profile can be directly compared, while Workout Levels within a specific Zone but different Workout Profiles can only be loosely compared. Workout Levels between workouts of different Zones cannot be compared. For example, a Threshold Level 4.0 and an Endurance 4.0 are not going to have the same RPE.

That’s quoted from here: Introducing Workout Levels: A New Way to Understand A Workout’s Difficulty - TrainerRoad Blog


I agree with Jarsson, potentially your FTP is set a bit high.

Are you completing VO2 workouts at level 6-7 over various interval lengths? Or mostly shorter ones?

Doesn’t mean anything other than that your progression level for Threshold is lower than 4.5.

Maybe. If this is a severe shortcoming, then by all means. If it’s just a relative weakness, IME focusing on improving weaknesses while neglecting my strengths end up making me an overall slower rider. YMMV.

" What does this usually mean, usually threshold and V02 are pretty close in terms of energy systems, no? And best way to build on this is focus more on threshold workouts I guess?"

This is an age-old issue related to estimated FTP based on a graduated exercise MAP test. I outlined the issue here:

Here is a repeat of that post in case you don’t want to follow the link:

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. :wink:
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."


It is probably true that your VO2 is over developed currently as folks say. It takes some work to really get comfortable with longer durations at sweetspot and threshold.

However, I also believe the VO2 workouts are scored a bit more on the high side than threshold. A 5.0 vo2 is not the same as a 5.0 threshold. And I think sweetspot is also high, so a 5.0 sweetspot will be a fair amount easier. When Leconte is just a 5.9, I think enough people have died on that hill know a 5.9 threshold workout is a pita. When Bluebell, a notoriously easy Vo2 workout is a 4.5, you can kinda see the discrepancy.

This is also my observation. Basically threshold around 7.5 and above is extremely hard. For example 4x20@97% is 7.4 and a I would say that is extreme for most people. 7.4 VO2 max is basically just another vo2 max workout. SST is even easier.

Over/unders are tough workouts, there are some variants I’ve done within TR that slowly ramp up the over vs an instant hit, so perhaps try those? Or dial it down 5% and see if you can complete then?

lot of good advice above, I’ve seen two reasons for that in my own training:

  • FTP set too high
  • not enough endurance/zone2 riding

Lately I’ve seen huge gains in top-end from doing 4-5 hours zone2 riding a week, but everyone is different!


I agree with this, too. This week, my workouts are Stevens-1 (Threshold level 4.4) and Estrela (VO2Max level 5.9).

Stevens-1 is 5 x 6 min at 105% with 3 minute recoveries. Estrela is 5 x 5 min at 106% with 5 minute recoveries. That’s only a couple of watts difference for me, so my guess is that I’m going to find Estrela a whole lot easier. We will see!

Just curious, do you ride VO2Max workouts differently from Threshold ones? Meaning different cadence, ERG vs slope, different gear ratios?

Higher wheel speed (big ring / small cog, and/or higher cadence) makes things easier in my experience. To a large extent (for me) even when keeping the gearing the same but upping the cadence, that will raise HR at bit at the same power output but still feel easier.

The same happened to me, basically turning SSBMV into 8 weeks of threshold. It didn’t end well.

Yea the threshold workouts are extremely difficult for how they rate it. See Black Hawk +4 as a 6.1

I think if you can do Black Hawk +4 your Ftp is probably a little higher than it is set at.

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