If you are doing a solo 20min test, shouldn't they be exactly the same? Or did you do it on intense rollers or something with steep downhills?

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"TRIATHLON ISN'T ACTUALLY THAT HARD OF A SPORT" -ALISTAIR

If you are doing the tests right (as a sustained effort), NP and AP will be very, very close. Pick one. It will not make that big of a difference.

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Twitter @achtervolger

The definition of FTP is based on Normalized Power.

Makes sense! Thanks (new to power)

I was looking at examples from various ride distances and difficulties. I was not taking in to consideration the sustained effort that the test is. If there is a large difference in #'s , you blew the test.

The intent is to find what power you can work at for the desired time. If it is 20 minutes for you, then the effort should be consistent for that 20 minutes. I would expect AP and NP to be well within 5% on an FTP test. Now, that does mean you have to pick your routes, etc. very carefully to get the required time (and distance) in with no stopping or dealing with traffic.

Good luck. FTP testing is not for the faint of heart.

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Twitter @achtervolger

The problem arises when people state their FTP from a local crit race that they did and think that it would be the same for a steady-state effort. As long as the test is a continuous effort, the differences should be minimal.

I'm pretty sure that AC is very vocal in stating that it's *average* power for a 1 hour TT effort - not normalized power.

On a 20 minute FTP test, you won't be coasting. So NP will equal AP, or be very, very close to it. Usually within 5 watts. Less if you do the test on a trainer.

The Authority wrote:

The definition of FTP is based on Normalized Power.

I don't think that's right.

The definition of FTP is based on the average power you can hold for an hour.

Here are the ways to determine FTP, from worst to best.

1) from inspection of a ride file.
2) from power distribution profile from multiple rides.
3) from blood lactate measurements (better or worse, depending on how it is done).
4) based on normalized power from a hard ~1 h race.
5) using critical power testing and analysis.
6) from the power that you can routinely generate during long intervals done in training.
7) from the average power during a ~1 h TT (the best predictor of performance is performance itself).


Soruce: http://alex-cycle.blogspot.com/...ven-deadly-sins.html

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CEO at TrainerRoad
Co-host of the Ask a Cycling Coach Podcast

On Wattage, AC has posted a few times that he tried to get Peaksware to disable NP for durations of <20 minutes. There is still potentially too great of a contribution from AWC in a 20 minute test for some riders.

AC also has disavowed the test method in the book as not being from a portion that he (AC) wrote and saying that taking some fraction of a shorter duration test conveys a false sense of precision when it comes to determining FTP.

Someone else already posted the 7 deadly sins.

If you want to use NP to set your FTP, have at it. If you're doing long intervals, 2 x 20 or similar, you'll know pretty quickly if you set FTP too high or too low.

The definition of Normalized Power is based on Average Power.

All of my FTP tests have been on a trainer and for all of them, NP is very close to AP.

....on your trainer AP and NP will necessarily be the same...you have no variation of terrain.

While highly variable terrain may well lead one to have significantly different AP vs NP, the normalized power computation is actually agnostic in regards to terrain.

Hugh.

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Genetics load the gun, lifestyle pulls the trigger.

Zombie thread resurrection.


While I know this statement is some years old, it's as incorrect today as it was then.

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

Would this be the case for 20 minute effort, close to or at FTP, which includes spikes of 60 seconds well above FTP every 5th minute?

Wouldn't that be an example of where NP does give a clearer idea of training intensity than average power?