I just completed a Zwift crit race in Cat B. It was just a touch under 21mins in length. Full gas from beginning. My FTP from a TR Ramp Test 2 weeks ago was 242w. Following the Zwift race trainingpeaks automatically recommended a new FTP of 279w. Same power meter (Tacx Flux 2) was used for both. I’m fairly positive if I used 279w in Trainerroad training plans I wouldn’t last. Particularly in over under and V02 efforts. I only just made it through Fang Mountain -1 two days ago at the 242w.
So, this raises a few questions. Should I accept a new FTP? Am I just terrible at ramp tests? Or is this just an anomaly due to it being a race. There were lots of fluctuations in the race with new PRs. Such as 292w for 20 mins. 494w for 5 seconds. 305w for 10 mins.
Thoughts welcome.
Stick with the TR FTP and bump it up if you need to, i.e. workouts are consistently too easy.
If you look at TR’s protocol for the 20 min test, you’ll see there are a few intervals thrown in there to deplete your anaerobic stores prior to the actual 20 min block.
I tried using the Zwift FTP from their ramp test in Trainer Road, and it went horribly. It is legitimately not sustainable. I’m not sure how Zwift calculates theirs, but it is not the same way TR does. Definitely keep TR FTP the same and only bump up if you find the workouts to be too easy.
Zwift uses 95% of the best 20min average power of a ride as a suggestion for your new FTP. A standard 20min FTP test includes some efforts prior to the 20min portion to deplete your anaerobic contribution and then using 95% of the 20min power. If you did a short warmup and then the race feeling very fresh, the FTP Zwift’s recommends could be quite a bit higher than you would get from a standard 20min test. I think in-ride recommendations from zwift tend be inflated / high.
I don’t know what model TP uses to suggest a new FTP, but for best accuracy you need to give most models a total full gas longer duration interval (20min) and a 3-5min within the timeframe of a week or so. If it doesn’t have a true standalone full gas 3-5min to go with the 20min most models I have seen will over estimate FTP.
How do threshold intervals feel at 242?
I find over/unders (palisade) and threshold intervals at 97-100% (lamarck) to be useful for evaluating how accurate my FTP estimate is. If they are tough but do-able at 242 I would stick in that neighborhood.
Thanks all. Much appreciated for the comments. The comments around the clearing 5 min effort makes sense. I went into the Zwift race fresh with no efforts beforehand so that could be why it’s giving a higher FTP. In terms of workouts in TR, this week I just made it through an over/unders workout so I think my FTP of 242w is on the money.
Cheers.
yeah the short answer is you pick whichever one you think is correct (i.e., actually approximates MLSS). Then it’s just about figuring out which is which 