I just did a race on RGT and it suggested a higher FTP based on my performance.
Is it “safe” to update my FTP in SYSTM, or would it be better to only have my FTP in SYSTM be the results of a 4DP test done in SYSTM? Is FTP calculated the same in both apps?
They are calculated differently.
RGT is like Zwift where if you do a hard 20 minute effort it does the standard calculations.
SYSTM still relies on the 4DP and Half Monty which are most accurate for the workouts in SYSTM. Since SYSTM workouts rely on all 4 4DP metrics you don’t want to update FTP alone based on the FTP from a different system/model. Instead you’ll want to retest in SYSTM.
Got ya’. Thought so, but wasn’t sure if Wahoo had developed a way to integrate the two somehow.
A very small expansion on the @emacdoug has said: RGT does those basic calculations in a slightly wider set up circumstances than just a 20 min effort - there is a lower threshold for the time period it considers… although I’m not sure exactly what it is. I am guessing they use similar equations and parameters to those in Intervals.icu and the numbers it suggests have been, in my experience.
That’s interesting cause I got an email from intervals in response to the same activity suggesting an FTP of 279 (+28), whereas RGT suggested 268 (+7)…
How do you get intervals.icu to send an email as you described? never had any email from them?? cheers
Not sure TBH. Check your account settings?
There’s a whole host of email notifications at the bottom of the settings page.
Might be worth checking your spam folder as most of mine end up there.
Thanks, yes got all those ticked. had a check back and I did get an email in October last year saying “nice ride” your FTP has increased by 8 watts. Nothing since then though, nothing in spam so will have a check around. cheers
Yes, that’s interesting - that’s a bigger difference to those I have personally seen. From what I recall from a bit of reading in the past plus some basic logic and/or personal interpretation: whatever any app or website says, it’s just a mildly educated guess to provide a figure that is itself a flawed metric of performance. If estimates of FTP vary using different models (or the same model with different parameters) then that isn’t a surprise or a particularly big deal. However, I am (i) not a proper cyclist/pretend virtual cyclist so may not be taking this business sufficiently seriously and (ii) I’ve had a few beers.
I have rarely had the combination of time and inclination to look in detail but things like this thread may be of interest:
Hope you’ve been well.
Did a few races on RGT lately where my average power exceed by FTP in SYSTM. Actual average power, not just an estimate.
Safe to update?
Your average power for what time period? 20 minute power? Typical 20 minute FTP tests multiple 20 minute power by 95%, so that would mean your average 20 minute power should exceed your FTP.
But 4DP power isn’t derived from that formula. Full Frontal has your do 2 NM sprints and a 5 minute MAP test first before you do a 20 minute power test which then allow you to take your straight 20 minute average power for that section. That does not always equal 95% of a standard 20 minute FTP test because the scenario and power sources can be completely different based on your rider type. It’s comparing apples to oranges because the scenarios are different between races in RGT and the 4DP in SYSTM. 4DP is supposed to properly tax your NM and MAP systems to give you a more accurate FTP number than just a straight 20 minute test which can be affected by your NM and MAP systems (depending on your rider type).
So, I wouldn’t take my 20 minute average power, even if multiplied it by 95%, and plug it straight into SYSTM. It’s more complex than that.
It was an hour long.
An hour of constant power output or did you vary up and down? What was the difference between your max power and min power during that hour?
https://strava.app.link/EY2vhEiByBb
https://strava.app.link/ZxC0pMlByBb
https://strava.app.link/WaAdZ3oByBb
https://strava.app.link/IBFnebsByBb
https://strava.app.link/u55ZRStByBb
Last tested FTP is 261.
I’m no expert but I would argue that you had sufficient time considerably under FTP during those 58 minutes to not warrant increasing your FTP by a few points (261 → 270).
I await further comments with interest.
FTP is really only one thing, max sustained power for an hour. Any other test produces a result that is scaled to an FTP number the test’s author thinks a rider with that result would have. Certainly this is backed up with some testing, but it only works for the average of the test cohort. e.g. The scaling of 20 minute test for pros will certainly be different than the scaling for hobbyist riders. Wahoo has not unified FTP calculations between SYSTM and RGT so best not to conflate the FTPs.
@mserge I think the better approach is to increase your FTP 1 to 2% for the next few workouts and see how it goes. Use the settings tab in the workout player.
In my experience there is less harm with a lower FTP versus setting it too high. Too high and you will blow yourself out quickly and set back your training so either retest or move it up in small increments.
Based on the difference in testing type and the designed usage I still wouldn’t recommend changing your SYSTM 4DP FTP based on an hour average power from RGT. Still apples to oranges.
@Coach.Andy.T @Coach.Spencer.R @Coach.Simon.B @Coach.Neal.H @Coach.Mac.C @Coach.Jeff.H
Don’t mean to blow you all up, but just thought to see if any one of you might be able/willing to chime in here. Apologies if there’s an article or something that discusses this I’ve missed…
