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?
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.
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)…
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: