FTP & Pre Fatigue

dan4280
dan4280 Posts: 5
Ah the perennial subject of FTP........

I have started using the 20 minute FTP test. I do a 20 minute warm-up then 5 minutes pre-fatigue at 120% of my last FTP result and then a 10 minute easy spin. Then I do 20 minutes all out and take 95% of this result.

My curiosity is around the pre-fatigue bit. The reason I chose 120% is looking at Coggan's table it looks like he basically says you can hold 120% of your FTP for 5 minutes. What do other people do for the pre-fatigue?

If I follow this I guess every time my FTP improves I will also have to up the pre-fatigue wattage. So last time I did the test I had an existing FTP of 241 x 1.2 = 289 for 5 minutes. I then held 268 for 20 mins to set a new FTP of 254. So I guess next time I test, my pre-fatigue has to be 254 x 1.2 = 305 watts.

Any thoughts? Maybe I'm getting too much like rain man with the numbers.

Comments

  • Aside from the obvious "why use FTP?", You might consider using the 30 minute test where you take the result from the last 20 minutes. That is, if you must use a test, b/c the power you can routinely sustain during long intervals is a better measure of FTP.
  • OnTheRopes
    OnTheRopes Posts: 460
    edited January 2019
    As far as I know Coggan says the 5 minute is a "all out effort" the percentages are just a guide and I wouldn't fixate on them.
    When I do it I just go as hard as I can for 5 minutes, like you are going for a long solo win in a road race or perhaps going for a Strava KOM
    Or try the 30 minute test as TA suggested.
    There is also the ramp test which is supposed to be easier to do psychologically and accurate but personally I have some reservations.
  • ...and if you are Rain Man then you might be better off just performing your intervals at maximum sustainable intensity (MSI) because that is what you want anyway so why put FTP in the middle of it?

    For example, if you can do 4 x 4 at 300W then do them at 300W. If you eventually find that you can do 5 x 4 at 300W, then increase power for the next workout with the goal of finding your new MSI for that workout. You can do the same with 4 x 8 and also use MSI for that as an indicator of LT that you can then use to set intensity for sub-threshold stuff...or not because you can use cardiac drift for that.
  • tonysj
    tonysj Posts: 391
    I follow one I think is off the BC site or some other site. Its long in adjustments of power and cadence during the 10 minutes warm up but here goes.

    4 mins of 175 Watts at 75 Cadence.
    10 seconds of 275 W at 90 C.
    50 Sec of 220 W at 80 C.
    1 min of 310 W at 95 C.
    1 Min of 175 W at 75 C.
    10 Sec of 300 W at 85 C.
    50 Sec of 250 W at 85 C.
    30 Sec of 180 W at 75 C.
    30 Sec of 310 W at 90 C.
    1 Min of 170 W at 75 C.

    FTP test of 20 minutes.

    No doubt some will say its "different" to others but I always follow that precise warm up so I know the stress build up to the FTP Test is exactly the same so should mirror a test that's as accurate as I can get.
    Tony.
  • TonySJ wrote:
    I follow one I think is off the BC site or some other site. Its long in adjustments of power and cadence during the 10 minutes warm up but here goes.

    4 mins of 175 Watts at 75 Cadence.
    10 seconds of 275 W at 90 C.
    50 Sec of 220 W at 80 C.
    1 min of 310 W at 95 C.
    1 Min of 175 W at 75 C.
    10 Sec of 300 W at 85 C.
    50 Sec of 250 W at 85 C.
    30 Sec of 180 W at 75 C.
    30 Sec of 310 W at 90 C.
    1 Min of 170 W at 75 C.

    FTP test of 20 minutes.

    No doubt some will say its "different" to others but I always follow that precise warm up so I know the stress build up to the FTP Test is exactly the same so should mirror a test that's as accurate as I can get.
    Tony.

    Your test is fine imo, so long as each test is the same.
    However to be useful to the OP you should state your FTP as watts alone is not very useful
  • tonysj
    tonysj Posts: 391
    OnTheRopes wrote:
    TonySJ wrote:
    I follow one I think is off the BC site or some other site. Its long in adjustments of power and cadence during the 10 minutes warm up but here goes.

    4 mins of 175 Watts at 75 Cadence.
    10 seconds of 275 W at 90 C.
    50 Sec of 220 W at 80 C.
    1 min of 310 W at 95 C.
    1 Min of 175 W at 75 C.
    10 Sec of 300 W at 85 C.
    50 Sec of 250 W at 85 C.
    30 Sec of 180 W at 75 C.
    30 Sec of 310 W at 90 C.
    1 Min of 170 W at 75 C.

    FTP test of 20 minutes.

    No doubt some will say its "different" to others but I always follow that precise warm up so I know the stress build up to the FTP Test is exactly the same so should mirror a test that's as accurate as I can get.
    Tony.

    Your test is fine imo, so long as each test is the same.
    However to be useful to the OP you should state your FTP as watts alone is not very useful

    Didn't think of that issue.
    Summer was at 294 Watts, 279 Watts after the -5%, although its probably a little lower now due to lack of riding with weather turning etc. I haven't changed the FTP figure in my Garmin just left it as is.
    I would struggle to give accurate FTP % figures to be honest as its the Watts I look at when conducting the test and dont tend to check or record the % figures.
    Tony.
  • Tom Dean
    Tom Dean Posts: 1,723
    ...and if you are Rain Man then you might be better off just performing your intervals at maximum sustainable intensity (MSI) because that is what you want anyway so why put FTP in the middle of it?

    For example, if you can do 4 x 4 at 300W then do them at 300W. If you eventually find that you can do 5 x 4 at 300W, then increase power for the next workout with the goal of finding your new MSI for that workout. You can do the same with 4 x 8 and also use MSI for that as an indicator of LT that you can then use to set intensity for sub-threshold stuff...or not because you can use cardiac drift for that.
    more complicated than using FTP with no apparent benefits
  • EBEB
    EBEB Posts: 98
    Re: pre-fatigue - I think the amount of fatigue will depend on cadence used. For me personally I know that my absolute best 5 minutes would be at a lowish cadence, but then that’d knock me back a lot for the 20. I’d shoot for a slightly higher cadence than normal for the 5 minute test so that recovery would be easier for the 20.

    The Sufferfest use 100% of 20 minute in their 4DP test, but then they also include a couple of sprints before hand. Are you managing to sprint at the end of the 20 or not? You can quite easily increase the average by going all out for the last 30 seconds & need to compensate. Personally, I’d just make sure you are completely knackered and barely hanging on at the end of the 20.