Understanding eFTP/eCP

[Luisma_Gallego_Soy_P]

I am reviewing and studying the implementation of various things in intervals and would like to make the comparison with wko5 mftp. The wko5 mftp usually has movement depending on the peaks you can do in a session. At 90 days if you have no data the mftp drops, if you do a glycolytic/neuromuscular effort (pmax, 30s, 1m) the mftp drops because its modelling understands that if you have more power in that zone, you are losing from the oxidative pathway, personally I don’t agree with this but it’s a personal opinion.

I understand that eFTP/eCP is based on CP, suppose as an example I have a CP through 3, 5 and 12 minute tests, at 13 days I do a very good effort in 5 minutes, I don’t see this reflected in eFTP/eCP.

I was wondering if this is the case or am I wrong.

Thanks

[WindWarrior]

WKO fits your MMP curve to a family of curves, and that defines your PD Curve. You can adjust the date range from as few as a single ride, to all of your time data. Doing that will change your MMP, which changes the mapping to the PDC curve.

By default the time range is 90-days, but you can have WKO do MMP curve fitting for a new PDC using any range of dates.

Here is 90-day WKO model for the day before and day of a glycolytic effort (Instructions were MAX Sprint 6 x 45-sec (30-sec off) )

mFTP increased from 238 to 247

A week or two before I did a “do 2x10-min pacing at your 20 min TT pace” which was 291W for 11 minute effort. This was January and I hadn’t been doing any threshold work. You can clearly see the drop-off at 11-minutes.

and then 5 days later a 32-minute long test where I ran out of road, but could have kept going as I was operating right at my threshold (276 for 32-min):

mFTP increased from 247 to 269. But not a max effort. Only a near max.

here is that long effort in Intervals:

and the MMP / PDC of just that 32-min effort in WKO5:

The coaches I know don’t always use 90-day PDC, and don’t rely on modeling for estimating. For example my “10-min pacing of a 20-min TT” effort was 291W. If that had been 20-min TT then 0.95 x 291W = 276W (0.95 is proper correction factor for myself).

And guess what? 2 weeks after that 2x10-min pacing effort I happened to do 276W for 32 minutes. Because I’m very good at FEELING how to pace intervals of 5-min & 10-min in relation to 20-min and longer efforts.

My personal opinion is that models are only as good as your understanding of how they work, and when to use them.

I’ve tried to map my understanding and control (time window) over WKO5 modeling to eFTP and Golden Cheetah extended CP. In general GC’s extended-CP is very close to WKO5 when I have a lot of good power data.

Here are the changes in eFTP from the 3 rides:

8 January: 2x10-min pacing of a 20-min effort

17 January: MAX SPRINTS 6x45-sec(30-sec):

22 January: long field test:

And GoldenCheetah:

266W eCP 2-parameter / envelope
278W eCP 3-parameter / envelope
265W eCP Extended / envelope

Re: your MSS I still have trouble understanding. For the 32-min effort (not max, could have gone longer) it estimates 237W. But I did 276W for 32-min and could have kept going longer, at least to 45-min, maybe longer. Of course your eMSS doesn’t know that.

Hope that helps.