FTP Increases TR vs. Zwift

I have an FTP question for anyone using both Trainer Road and Zwift.

In October my FTP test placed me at 274.
I completed Sweet Spot Base Build, and my next FTP Ramp test indicated FTP 268.
I did not drop it and have kept it the same with solid success.
I am currently in week 5 Low Volume of XC Olympic Race.

Rather than switch to a mid-volume program, I am also doing Tour de Zwift for fun and to push myself. I am not using Zwift Structured Training. Last week after a stage Zwift upped my FTP from 271 to 281.
After riding last night, Zwift upped my FTP to 301.
(My power was over 320w for most of the ride, my cadence was 80-110rpm, this is obviously because of Trainer Road !)

I have been completing my TR workouts well, and I likely need to raise my FTP slightly.
I CAN do another ramp test, but now is not. great time in the middle of the program.
My HR in TR during VO2 work is never zone 5, never as high as the Zwift races.
I have been working to increase my riding cadence up to 105+rom and to comfortably push my HR over my usual zone 4 during intervals and races.

Has anyone used recommendation from Zwift to adjust their FTP in TR?
Moving to 301w seems very high to me.

I was thinking I would raise TR by +5w and see how the next VO2 workouts go.

I am using a 2018 Kickr, Wahoo Cadence sensor and wahoo HR monitor.
I usually run TR on my iPad, and Zwift on my Mac, all connections via Bluetooth.
I alway FTP test in Trainer Road; the last 2 tests using the ramp method.

If anyone has experience with these comparison I would like to know what they tried.

M.

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Out of interest what hardware are you using? Powermeter, smart trainer etc?

  • What precise test did you use and in which app was it run?
  • Presumably this was done in TR?
  • Note: Zwift does what I consider to be bad practice. It simply takes your best 20-minute power and applies the 0.95% multiplier (that is typical with a standard 20-minute FTP test protocol).
  • This is important, because the proper 20-minute test includes early efforts intended to pull out the anaerobic contribution from the long 20-m test.
  • So, I feel the Zwift auto FTP from rides/races is fraudulent and likely overstated in nearly every case. I recommend discarding that every time, unless you really know that the effort from that was not influenced from anaerobic contribution.

It is great to use both apps in any way you want for fun and training. But that said, I feel that testing should be done consistently with the same app and the same protocol each and every time. Mixing sources is destined to lead to confusion at the least, and problems at the worst.

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This!

Take the Zwift “FTP” with a pinch of salt and test again with a proper protocol.

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While it’s true that Zwift just uses 95% of best 20 minute power, which is wrong, it does sound like you might have a legitimate FTP increase. Look at the power data for that ride. You say you averaged 320 for most of the ride. What stage was this (how long were you holding 320 W)?

Zwift can be a lot more motivating, if that’s your mentality (it is for me). The low HR for VO2 work suggests this might be the case.

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How far away are you from your next ramp test?

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I would try with 285 as FTP

Thanks for the feedback!

I am using a 2018 Kickr, Wahoo Cadence sensor and wahoo HR monitor.
I usually run TR on my iPad, and Zwift on my Mac, all connections via Bluetooth.

I alway FTP test in Trainer Road; the last 2 tests using the ramp method. I test as scheduled. I warm up the trainer for 10 min, spin down, then FTP test for each test.

On Stage 7, my power was averaged at 311w over the entire 46 minute lap, 318w over 20 minute interval, 328w on 5min, 244w on 1 min. Avg 3.0w/kg (compared to 2.7w/kg on stage 5)

Trainer Road is my primary tool; I will not adjust based on a Zwift recommendation alone.
I did review the Zwift 20-minute calculation method versus TR old and new ramp test and I appreciate the new method of ramp calculation.

I don’t have another ramp test inside this program, and no tapering from this week to the end week. I suppose I could taper fora. few days, and then retest on ramp. That means I would not finish and taper before my March trip to Utah, but I guess that is not essential.

M.

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Ok, so you can expect a pretty accurate assessment of your FTP using that equipment plus trainer road. It all depends if you trust the zwift figure

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No I definitely don’t trust the value, I was more interested in the fact that it reported such a big jump and what I should do with my TR.

I guess what I’m thinking is that I need to uppitiest [not sure what the preceding word should be?] my TR, but I don’t want to interrupt my program by ramping down a week for an FTP test.

I was just wondering if others have made some adjustment based on secondary feedback.
(in this case form Zwift)

M

Anytime you feel you may have an FTP change (up or down) you can test by using the Workout Intensity adjustment and see how a 1-5% change feels, with respect to the intended workout. If your adjustment feels good, apply that same percentage change to your actual FTP.

Or you can simply adjust your FTP by similar amount initially, and still evaluate how the workouts feel. Two ways to get to the same conclusion of testing a predicted adjustment.

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From reading through your posts it suggests that you ‘may’ have underperformed in your ramp test seeing as you have found the workouts relatively ok. As Chad suggests a small bump in intensity is a good way to see if you can cope with a higher FTP. If you’re ok after a few workouts then bump your FTP manually

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One way I like to assess and check my TrainerRoad ftp is to race a Watopia 3 lap race which typically takes 50’ so is a good check. Also I assume you did a spin down calibration on the kickr?

This fact alone suggests that you should manually adjust your FTP higher.

Remember the ramp test is optional. It’s perfectly okay to manually reset your FTP based on RPE and HR experienced during threshold and VO2 workouts.

Something like Mary Austin (and how well you survive it/are crushed by it) is as good a yardstick method for assessing whether your current FTP is set too high or low or just right, in my experience. In the context of Trainerroad, your absolute FTP number is only important as a setting for workout intensity, nothing more.

Good luck, you sound like you are going well!

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And having done Lamarck last night (4 x 10 at FTP) I’d say that this workout is as good an FTP assessment as any - Chad even says so in the narrative.

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“With a grain of salt.” Sorry, had trouble ignoring “pinch.” :wink:

They both mean the same thing :wink:

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It’s pinch!!

Haha!:smile:

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There’s not a grain of truth in anything he says!!!:wink:

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Personally I think people shouldn’t confuse one system with another, just stick to one for your performance tracking and if you do enjoy Zwift as well just treat it as something else that is likely helping to improve your capabilities. Wherever possible you should replicate the conditions exactly when testing, this should help keep things consistent. So, same time of day, same rest period, same equipment settings etc. Throwing in different packages and even zwift races to extrapolate potential new changes in FTP is just wrong.

From experience of reading people’s posts, they see a bigger number and really want it to be true, probably not the case here but it’s a common theme.

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