20min FTP test with ERG Mode

I have an FTP test coming up and want to use the 20min test - as that is what i have used previously and i think it helps me as an individual get a better result.

I know the workout automatically switches to resistance mode when the test starts but i would like to use ERG mode as i heard the guys talk about the benefits of this in a AACC podcast in terms of pacing and goal setting.

Could anyone link me to that episode? (or any others where it is discussed?)

I tried the @chado search on SC but couldn’t seem to find it? maybe i used wrong search terms?

Any help would be massively appreciated.

1 Like

The problem with using ERG mode for the 20min test is that you are then testing for a particular number rather than trying to find your true FTP. In ERG mode, you will be locked into 102% of your current FTP when completing the 20min interval; you cannot go any higher. If your FTP is set to 200 in TR prior to the test (just an example), ERG mode will vary the resistance of your trainer to make sure you are putting out 204W for the 20min interval, no matter how fast you try to spin. At the end, your FTP will be computed by taking 95% of your average power for that interval (204W), which comes out to about 194W. Your resulting FTP is then completely determined by the FTP number set prior to the test (and it will end up being lower!).

They recently recommended using ERG mode during the FTP ramp test, because that test dynamically scales to match your fitness, whereas the 20min test does not. ERG mode is immensely helpful when completing almost every other workout, but the 8min and 20min tests are two “workouts” that should never be completed in ERG mode.


thanks for your input !

completely see your point and agree BUT … my plan was to use workout intensity to bump up the target a fair few % points to help pace the effort …

I can not recall (or find) the podcast where they advocated this … but i feel it could be a good pacing strategy after the guys recommended …

Ah, that makes sense. If you haven’t tried it, I recommend giving the ramp test a go at some point. I tested much higher than I expected, and if I had done the 20min test I definitely would have sold myself short due to mental expectations of what my FTP should be. Turns out the number I got from the ramp test was spot on, almost done with SSB I now.

Sorry I couldn’t help find the podcast you were looking for, I’m sure someone else will chime in with an answer soon.

Thanks for your advice! I am a little nervous about ramp test as

  1. When I did it 8 weeks ago my FTP generated was about 40w lower than what I’ve been able to train at the last 2months

  2. I seem to be heavily skewed towards more threshold/steady state efforts. And struggle with High end VO2 type work.

(I did manage to build my VO2 workouts up to 120% during last block but took me a while-meanwhile the Sweet Spot & Threshold was fine straight away)

Sorry Long answer.

I always thought that the software automatically transfers to slope rather than ERG mode during the 8 / 20 minute intervals on the FTP tests.

I’ve used erg mode in the 8 and 20 minute tests, but I plan to stick with the Ramp Test from now on. For the 8 and 20, erg mode lets you keep a steady pace and you can increase or decrease the intensity using the up and down arrow keys in Windows. I don’t know how you do that in the other platforms. It might also be helpful to know that the M key lets you switch between erg and slope (aka resistance) modes.

Crownan is right, on a smart trainer during the FTP tests TrainerRoad automatically switches the mode from slope to ERG at the right points in the program.

Hey - thanks for your reply!

yup i am aware of this - but i was keen like @nju001 mentioned to use ERG mode and use +/- intensity to help pace …

i do remember the podcast discussing this and it sounded like a good plan but i can’t find the episode anywhere? any clues @chado ?

I found a little discussion of this in Podcast 158. I think there was an earlier podcast where Chad mentioned that he used erg mode for a test during one of the classes he taught.

My recollection, which could be flawed, was that @chad didn’t recommend testing using erg mode in the podcasts but had mentioned that it wasn’t recommended but ”could” be used to “confirm” ftp and only for those that are very familiar and experienced with it.

1 Like

Correct. I/we don’t recommend it, but it can be done if you’re reasonably experienced and are willing to adjust the intensity of the intervals based on achieving your highest, sustainable work level for the 8- or 20-minute assessment interval(s). I’ve done some solid assessments in Erg mode over the years, but I’d also done probably 20 assessments in slope mode by the time I felt I could use Erg appropriately during an FTP test.

1 Like

Thanks @chad … i had heard you say it could be done … maybe i haven’t done quite enough assessments just yet … only done about 4-5 …

Great as ever to have your input.

I will shoot for slope mode and hope my trainer co-operates well in non ERG mode …

1 Like

I found doing ftp tests in resistance mode to be nearly impossible and the results were dominated by issues with shifting and trying to maintain a steady pace when the power and cadence numbers were jumping all over. That’s why I was happy with the introduction of the ramp test.