Did WKO5 calculate a wrong FTP from 20-min test?

After doing a 20-minute FTP test this past weekend on a Cyclops Hammer, WKO5’s mFTP came out at 96.7% of the average power. This is +5 watts more than I thought it would be, per the 95% rule. The files from TrainerRoad, TrainingPeaks and WKO5 all report the same average power. I know the 5-point difference is nominal, but would like to understand WHY the variance? Anyone know what is going on here?

Do you have minimal short duration maximal efforts? This would be why mFTP comes out higher than expected after a 20 minute test.

Your phenotype probably is TT and your FRC is probably low I’m guessing.

Go rip a few 45-180 second efforts at max watts and see what the model does.

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mFTP in WKO is based on your entire power curve, not just 95% of 20min. You probably have some strong shorter duration efforts in there. Mine is a fair bit high as well.

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It’s the reverse. A mFTP that is a high percentage of 20MMP is indicative of low FRC.

Or the TTE is really low.

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Right. I was guessing high mFTP low TTE, since that’s what I’ve typically seen. My 1-10min power tends to pull my mFTP way too high in WKO. Strava tends to give me the exact same estimate so must have similar modeling.

Either way, I take them as vanity numbers and train with an FTP right near my hour power.

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One thing that is confusing in the latest release - the stats like mFTP in hero bar will change if you select Road vs Indoor:
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Thought I was going crazy last night, and then found that the hero bar will show separate mFTP for Road and Indoor. However the charts still work as expected, and show mFTP for all activities.

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Correct on all fronts! Have not done hard intervals <2 minutes for the past 90 days. I was also wondering why the FRC was so low relative to over the summer; you answered it.

Based on all this, I think more accurate to base training off the 95% calculation rather than the higher mFTP. Advise if you think otherwise. Thanks!

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After summer layoff I didn’t have any hard efforts under 2-minutes, and FRC dropped to high 9s. Then per the Power Duration Model about 6 weeks ago I did some hard efforts targeting 70 seconds and FRC jumped into 15s. #FeedingTheModel

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That’s probably the safer way to go.

Sounds like your situation is more what @stevemz described. It’s funny because I’m also categorized as a TT phenotype but have a decent FRC. My short power (<10min) seems to lead to a low TTE and overly ambitious mFTP even with a fairly well fed power curve :man_shrugging:

So just starting back on the bike after a 2 yr hiatus. I have about 10wks of rides in system but the mFTP is ~60 watts above what I know it is on the bike. Because of this huge difference using the program to actually plan my workouts is impossible. Is there a way to temporarily adjust my mFTP to my bikeFTP or just get usable info from WK05??

You have a power spike somewhere.

Post the power duration curve for the past 90, 60, and 30 days