kJs is not a good way to measure the difficulty of a workout, even in the same zone.
And we validate this with workout outcomes and we’ve tweaked the adjustment a few times. We want people to have productive workouts to get faster and achieve their goals.
We know this method works by the amount of success our athletes have had (large fitness increases, national championships, world championships, personal goals achieved, etc.).
The good news is we don’t force anyone to do it. So if you’d like to do your own testing protocol, get an FTP increase, and keep your threshold at the same level then go for it!
That seems like the wrong solution, because IMHO you haven’t identified the actual problem in your post.
TR’s FTP does aim to approximate the lactate threshold, because the purpose of this value is to set your training zones — using Coggan’s model.
The actual problem as I see it is that people use TR’s FTP as the main metric for fitness. Rather than renaming things, adding to confusion, I’d invest in creating and surfacing better performance metric and make those explicit to users. These should depend on the plan and your goals. E. g. if an athlete chooses a crit plan, then absolute short term power and repeatability are metrics. How often can you go above threshold and recover?
This would also help you tailor plans to the needs of the user. E. g. I have added a polarized block to my training after my drop in endurance, because my problem in May when I restarted training was not power, but endurance. And in my experience, a polarized block improves my endurance but doesn’t raise my FTP much.
I realize this is a HARD problem, but renaming FTP to tFTP does nothing to address it and just causes further confusion once someone digs deeper. (What is the difference between FTP and tFTP? But if tFTP isn’t the same as “Coggan’s FTP”, why does TR use Coggan’s zone model with tFTP = FTP? What is FTP really?)
Bingo.
TR and its athletes need better metrics. Too many of us are chasing power. Even though I am aware that FTP is not the only performance dimension that matters, it is really hard to quantify progress in the other dimensions. E. g. last year I did a power PR (117 % FTP for almost 7 minutes and an average heart rate of 159 bpm — and I had energy to spare). But how do I quantify that? Should I repeat the climb to assess certain aspects of my power?
I would like this, it would help to give the athlete an idea on how their aerobic fitness is progressing. Depending on how your body adapts to a given block, you might see a big jump in your tFTP but your actually 60-minute power might not change very much.
Think of it more like a constant progression where we are either moving your power up and/or out depending on your goals and place in your plan.
Then there are occasional small jumps after you recover and we detect an increase, but not such a big jump that it crushes you.
I like the weight training analogy. You squat 135 at 3x10. You then put 145 on the bar and you might get 1x10, 1x8, and 1x6. Then you work it back up to 3x10 but are at 145 lbs this time.
Bingo.
TR and its athletes need better metrics. Too many of us are chasing power. Even though I am aware that FTP is not the only performance dimension that matters, it is really hard to quantify progress in the other dimensions. E. g. last year I did a power PR (117 % FTP for almost 7 minutes and an average heart rate of 159 bpm — and I had energy to spare). But how do I quantify that? Should I repeat the climb to assess certain aspects of my power?
I can agree with that, even after three years of consistent training my threshold power is comically low compared to my anaerobic power, that’s why I would like the added metric Nate proposed. I know it’s not for everyone but the whole three day test does help to paint a good picture of where your fitness really is, e.g. day 1 sprint/anaerobic test, day 2 5 minute test, day 3 20-minute test.
I’m probably the wrong person to game this with because, honestly, I’ve been training for several years and I’ve NEVER had an FTP that I thought I could hold for 60 minutes (whether it’s from an 8 or 20 minute test or a Ramp). I just see FTP as a number to base workouts off. I was more speaking to the constant debate I read on the forums.
I do very much appreciate that TR listens and tries to solve these issues though!
Nate probably has the numbers on this, but there are outliers and they’re probably the most vocal about setting FTP correctly. If you’re not an outlier or if you fit well in that bell curve, you’re probably not super concerned about the number that AI FTP or the ramp test gives you because it’ll probably be just right.
Regarding the TR team, I am VERY thankful they take these issues seriously and actively communicate with the user base!
I’m liking tFTP right now. I know it’s similar…but honestly it’s mostly the forum people who want to see it change.
Zwift educated tons and tons of people on what FTP is, even if they aren’t using it as a true 60-minute power. Us changing the name too far away from FTP would cost millions and millions of dollars to educate people about the change, and the benefit would most likely just be so forum people can sleep better at night.
Like why not spend that money on some more data engineers and data scientists!!
In fact, we can probably just have a support article calling it “Training FTP” that can be linked in the “?” by FTP and discuss the who debate about threshold and FTP and how long you can hold it. Then keep having the words “FTP” everywhere else.
We have this internally and we call it “Fitness Score”. It’s a combo of your FTP + PLs + Weight.
Then you get an arbitrary number that you can see go up/down. It has very fine grain sensitivity and can be used as a metric to know your performance is improving and you’re getting faster!
IE for me, I had a high Fitness Score of 1,226. And before Cape Epic I was around 1,149, or about 6% off of peak fitness.
We need outside PLs first, but I think this could be a pretty cool way to show small fitness increases and motivate people to stay consistent.
Whenever this gets released (can’t wait), will it be able to show us our historical scores? Would love to see it over time… as least as long as PLs have been out.
