Oh, I wasn't questioning Marc's knowledge. I was just pointing out there are an awful lot of ways to estimate FTP, and more get proposed all the time. As I said 15 years ago, whichever method you choose, you should probably do that consistently rather than switching among the various methods.

If I may make a few observations based on a few years reading this literature I would summarize as follows.
(disclosure: some of these are not my original observation but from a colleague who is much smarter than me regard testing and training but who does not want to be named here).

1. There is no perfect FTP test, each one has pros and cons, so there aren't really any deadly sins, just different methods which are all estimates. Without a true agreed gold standard, we don't know the true accuracy of any test, so it almost impossible to be 100% sure which tests are best for whom.

2. There is no fundamental "threshold" on the power duration curve, and definitely not one set at a specific time (eg 8mins, 20min or even 60mins) for everyone. The curve is complicated as will be known to anyone who has tried to model it mathematically across a large sample of riders

3. There is no entirely linear (aka flat) area of the power duration curve and it is probably not very useful to model it in a linear way (eg as a percentage). Indeed there is very rarely anything entirely linear in human physiology.

4. Research from various large sources shows around 90% of non-pros do *not* manage to achieve 95% of their 20minFTP test power in a 60min maximal effort. Heck 90% of non-pros don't do a 60min max effort, but lets ignore that!

5. The definition of FTP doesn't tie up with any known physiological measures in most (but not all) research studies, including this one, which is not a perfect study (is there any such thing?)

6. The entire concept of "lactate threshold" is probably incorrect or perhaps a huge oversimplification, no lactate testing protocol especially those with a fixed value (eg 4mmol/l ) has really proven that useful in itself (although they can add additional information in some circumstances)

7. The entire concept of "anaerobic threshold" is a huge oversimplification; in short energy systems overlap much more than previously realized and are hard to separate into distinct steps in reality.

8. The concept of FTP was once useful when the field was young but as with many early concepts but now, not so much. Further it is often misquoted which is a fault of those who both those who misuqote/misunderstand/misapply AND those who provide or perpetuate a vague definition without seeking to improve it for the benefit of the entire community.

9. The concept of FTP is mainly flawed because a. there is no threshold in the way commonly understood b. "without fatiguing" is plain wrong in the way that fatigue is commonly understood c. there is no precise time definition in the phrase "about an hour" d. there is no robust physiological verification . However FTP seems to be a more handy phrase than .......a convenient point on the power duration curve or CPPDC :)

10. The science of cycling and the science of human physiology is never perfected and never fully known. Therefore no individual (and no group) is the font of all true facts, rather the entire field evolves, and everyone who has a constructive comment, or can conduct a study contributes to the field and should be welcomed, not criticised or flamed or shouted down.

that's all, have a good day!

A lot of points made and I'm by no means astute enough to discuss other than my training will still center around the concept of FTP even if I don't have a full grasp on it or the most precise method of testing. If it was once useful, meaning there are plenty of guys and gals that have progressed using the concept, it cannot go bad like milk that would sour or bread that would mold. In training if it is effective once it does not lose effectiveness. Other new training concepts may come about that are more efficient in getting to the goal, but the old concepts do not suddenly become ineffective just because a new one has come around.

Coming from the world of strength training and being a successful competitor and helping others prepare and win I still use strength training concepts from back 30 years ago based on training set by 1RM. Just as training using an estimated 1RM is to a lifter, FTP or CP or similar has been to me as a cyclist. Both strength and endurance train at a certain percentage of this supposed limit with the goal of raising that limit. Whatever one wants to call it I don't care. What matters to me is that I am seeing positive trends in WKO4, but more importantly finishing time and endurance is improving out on the road. Under the concept of FTP. I am no doubt guilty of misunderstanding a loft of concepts in endurance training since that is not my primary training, but I see no reason to walk away from it.

You could just say you don't agree with the FTP concept because much of what you have written is not correct

You mean a measure of power itself?

Sure there is a PPP in there somewhere!!!

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Hamish Ferguson: Cycling Coach

Great answer that covers so many concepts.

For me, FTP is useful number that I can use for my comparisons. Whether I'm working on my power, my capacity or recovery it's good to know that day's %FTP along with other numbers and whether I'm trending up or down.

Thank you for taking the time to write such a complete answer.

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Indoor Triathlete - I thought I was right, until I realized I was wrong.

Curious how much of our understanding of FTP and what we try to estimate based on 40k rather than 30k or 100k being the time trial measuring stick?

It's a little like Churchill's thoughts on democracy: "Indeed, it has been said that democracy is the worst form of Government except all those other forms that have been tried from time to time."

Using FTP is simple and straightforward. I haven't heard a better alternative being proposed.

Yes, it's quite functional. Unlike...

Just for s**ts and giggles I did a proper CP test today. One short and one less short (pretty unfit) tte test. Funny seeing I have never performed a scientifically determined FTP test.

My thoughts.
Done indoors: not functional.

Done at a fixed power: not functional.

TTE: not functional.

Done at a low cadence: not functional.
Sitting upright: not functional.

Done on my road bike: not functional for time trialling or track.

No fan: not functional, possible except for hot indoor velodromes or climbing sheltered climbs.
Oh, if only there was only a functional way of measuring power at threshold.
Hamish

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Hamish Ferguson: Cycling Coach

It never made Andy's original list, but he did acknowledge it had validity (within a given ratio range) in this June 2004 Wattage post such that it could be added:
https://groups.google.com/...OkTP7-I/9i5fveOBGfAJ


Of course "8 deadly sins" doesn't sound quite so catchy.

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http://www.cyclecoach.com
http://www.aerocoach.com.au

It's an interesting thing to discuss.

Most of those involved in exercise physiology I see having a dig at FTP are those who champion Critical Power as being reflective of a "better" threshold (and is at an intensity a bit higher than FTP). A threshold they say is related to maximal steady state VO2 kinetics rather than say, maximal steady state lactate or other physiological/metabolic markers.

I'll leave it to them to debate the relative merits of each.

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http://www.cyclecoach.com
http://www.aerocoach.com.au

Good thing I still use 220-Age for estimating FTP.

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USA Triathlon Level 2 Coach
Slowtwitch Master Coach
Head Coach, TriCoach Colorado, LLC

Fixed it for you. Accuracy counts when estimating these nebulous concepts.

My personal take-away regarding anything outside a 1 hour test is it’s a great estimate. It’s going to give you a number to shoot for and something to work with.

I recently did a ramp test and realigned my workouts accordingly... I had my first workout last night with two 20 min sessions at 95% and I’m skeptical at my ramp tests accuracy to give me my true 1-hour power, but you know what? Now I know the ramp MAY have overshot.

Nothing is absolute, and even a 1 hour test you can still overshoot or undershoot your ability for that hour and not come out with that accurate number.

To me ftp is a general number I base my cycling off of, knowing it isn’t necessarily the most accurate thing given circumstances at any given time.

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80/20 Endurance Ambassador

If you had a magic wand and could get a non invasive device to measure, lactate or VO2 or....... what is your belief the best measure would be to set this "threshold".

I was joking around. Alex S gave a nice critique of the 2 camps. What you said is what most people do, including me. Pick a test, train and see if your number improves. It's just that what test you chose, how you got that number, what the number means and how relevant it is to your race or what you want to achieve is still a work in progress. Personally I love science and research so I'm not phased by contoversy except when it gets personal, which it unfortunately usually ends up being. So far so good on this thread.

Here's a nice paper that's recent and on this topic.

https://physoc.onlinelibrary.wiley.com/.../10.14814/phy2.14098

Power output is the integral of all these underlying factors, so I'm not sure anything is better than the power we can already measure as it's the ultimate expression of physiological capability.

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http://www.cyclecoach.com
http://www.aerocoach.com.au

But "better" depends on what question is being asked. Power output is very, very useful because it's so closely tied to performance. But it's not great at answering the question, "Why?" E.g. if my power for an hour increases by 2% after some period of training I don't know whether it's because I'm more efficient, have higher aerobic capacity, higher anaerobic capacity, etc. Answering those questions can be useful. If I had to choose just one, I'd pick power. But I don't think it's exclusive of the other metrics. If there was some non-invasive watch that could measure my lactate, that'd be nice to add to the mix.

If your 60-min MMP improves by 2%, it won't be due to a change in anaerobic capacity. To do that you'd have to at least double your anaerobic capacity.

As for efficiency, you'll need gas exchange measurement and that's an invasive process.

The most likely culprits for the improvement will be a training induced increase in VO2max and an increase in fractional utilisation of VO2max at threshold.

Something as simple as a power profile will go a long way to answering those questions, and more importantly, suggest what training intervention will be more suitable (when considered in context of other stuff such as training and health status, time of season, nature of event goals etc).

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http://www.cyclecoach.com
http://www.aerocoach.com.au

If we are to believe Sebastian Weber's work, an increase in your anaerobic capacity without an increase in VO2max will decrease the point at which lactate is in equilibrium and accumulates. Your fractional utilization of VO2max is dependent on your anaerobic capacity. He's got quite a good coaching resume, as well as Dan Lorang who got his coaching start under Sebastian if I am remembering correctly.

Can you explain "dependent" please?

I fail to see what a coaching resume has to do with anything discussed here.

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http://www.cyclecoach.com
http://www.aerocoach.com.au

As best I can remember, the max rate at with you can utilize your glycolytic pathway, will be major determinant of where your fractional utilization of VO2 max lies. As it goes up, the fractional utilization goes down. As it goes down, fractional utilization goes up. If your glycolytic utilization goes too low, you could probably be limiting your VO2 max since the aerobic pathway to oxidize pyruvate/lactate is faster than for fats.

Sebastian is PhD, and well published in the relationships between our aerobic energy production pathways and anaerobic energy production pathways. I brought up the coaching part as real-world results as opposed to just lab results.

Thanks for the clarification.

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http://www.cyclecoach.com
http://www.aerocoach.com.au

Yepp, measuring power is a good indicator of performance, but not on how it is created! The best measure of high performance in many sports is speed. For example in an ITT - the most direct measure is "who is the fastest". BUT: we all came to the understanding that the speed is composed by many factors, in short mostly power and drag. Therefore we look at power, but:

Power is showing you how you are training, not how to train!

This is a very important difference! Power is the outcome, the result of a certain (physiological) ability of the athlete. When you want to increase power, you NEED to understand how it is created. Just as with speed - commonly accepted that we look at drag (e.g. aerodynamics) & power as we want to ultimately understand how the speed is created in order to increase it.
It has been a similar fate with the original lactate or anaerobic threshold: invented as a marker of performance, it was getting more and more popular to use it to prescribe training instead of only monitoring it.
People are tempted to do the same with power: a great metric to monitor training and performance getting alienated as part of the search for the ability to make informed decisions on how and what one should be training.

Re anaerobic capacity: it isn't really anaerobic capacity but the ability to produce power in the glycolytic pathway. Increasing this ability will - given that no other physiological parameter change - lower performance (power if you want to take it this way) at anaerobic threshold aka max lactate steady state. I assume this is what Bioteknik was indicating

Yes, but is there a direct relationship between anaerobic capacity and glycolytic ability? I guess there are biomechanical and metabolic efficiencies that also determine pace/power for a given unit of energy but the amount of energy per unit of glucose is a constant. I guess I'm more of a biochem geek and not as up to speed with my physiology.