I meant what services use CP.
CP is baked into GoldenCheetah analytics package.
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In and of itself, CP in isolation is no more useful than FTP is useful – but generally we think of CP as being jointly determined with W’, so there are actually two parameters (CP and W’) not just one (FTP). CP and W’ together give you some idea both about your aerobic and anaerobic capacities – FTP as a single number, doesn’t make that distinction. CP and W’ together give you a way to predict power at different durations; FTP doesn’t (except at the well-known rule of thumb for 20 minutes). That means that it’s easier to use CP and W’ to make pacing plans. And from an estimation point of view, CP and W’ give you a way to evaluate how reliable they are, and how to update the estimated values when you get new data.
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sure but a quick FTP estimate is one test. A quick CP estimate is bare minimum 2 tests, really its 3 tests.
CP is published math, while WKO power duration model is not.
The TP protocol for FTP requires a 5 minute blow-out before doing a 20 minute test. If you have to do a 5 minute blow-out anyway, you might as well do a quickie CP/W’ test with the 5 minute max blow-out, then a rest, then a 12 minute test.
My protocol for FTP testing isn’t the Hunter Allen protocol… But if you do follow the actual Hunter Allen protocol, where he wrote it was a 5-min vo2max estimate first and foremost, then a 20-min test, yeah I guess. But mixing 2 max efforts on the same workout is a non-starter for me. Tried it with INSCYD.
Good for you. That’s probably wise.
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Coach Tim Cusick’s WKO testing is better IMHO. But my WKO license is bought and paid for, if I wanted to be free as in beer, would do the CP test.
My coach and I never go down ratholes like this. A lot more discussion on how I feel, how efforts feel, how to make time for more training. What’s it like being in his shoes (performance and race director, getting to go to Europe a few weeks ago, etc).
Go out and consistently do the work. Push up volume. Occasionally do some max efforts. Watch fitness slowly increase. Sometimes its glacially slow. Play the long game. Patience is a virtue.
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So, the W’ equals how much work someone could do below CP, and CP would be the flat but so maybe 309W in this case (no maximal efforts in months)?
100%.
People are chasing after definitions and details that won’t make a meaningful difference in how they train, let alone how they perform.
IMO, of course. 
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In some ways, FTP (or CP) are ways to make it easier to communicate with a coach or other riders–if you’re tuned into yourself and have learned over time what a particular effort is “supposed” to feel like, you might not need a power meter at all. Nowadays lots of riders think that they need hyper-structure for their workouts, and if you’re one of those kinds of riders then lots of levels and precise fealty to a particular workout is probably what will make you happy. If you coach yourself and are meeting your goals with looser protocols, you might not need to do this nutty stuff at all.
I haven’t done a formal FTP test since sometime around 2007. I think the last time I did a formal CP/W’ test was maybe 2020 during the first COVID lockdown, but that was just cuz I was bored and spending a lot of time on the indoor trainer. I mostly don’t do hyper-structured training so I don’t really need to peg my workouts to a particular number and then evaluate how closely I come to the prescription.
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Right. Learn how to pace 1 to 5 minutes in 1 minute increments. Learn how to pace 10 minutes. Learn how to pace 20 minutes. Occasionally go out and do a long effort, something over 30 minutes. Big picture is easy - do long steady rides plus a couple/three days of short/hard intervals, then start doing short and fast, then long and fast. Race ready.
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Almost. W’ is how much work above CP, and CP is (in an ideal world) the flat part. But does your app allow you to plot not power on the y-axis and log time on the x-axis but instead work on the y-axis and time on the x-axis? Try that, and you’ll see how linear the relationship is for you. For most of us, it’s pretty linear (and then starts to curve downward).
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Exactly. People need to remember that what makes them happy, isn’t always what makes others happy.
I’ve seen CP mentioned a bunch, but don’t really understand it all that well and it’s application. That doesn’t mean it’s not useful to others, or more importantly that I can’t increase my knowledge base by learning about it. Even if I don’t end up using it.
Same with the whole Z2/LT1 mess.
Thanks for that. I’ll have a looksie. I’m using Intervals.ICU so only have what is generated there.
Are you using the W’ value that’s generated by ICU? For me it would be the ~12000kj? Mine’s blank when I add it to the activities graph.
Yeah. NIce example. This is if your CP/W’ are well-estimated of course but, if so, that’s exactly how you can use the CP/W’ model to predict how long you can hold a surge. It’s not something FTP lets you do very easily. And, if you can’t hold it (or you can hold it for longer than predicted) that tells you something, too.
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Super interesting stuff.
I’ve plugged in 22330 into a few rides and don’t go anywhere near zero.
Between that, and discovering another “model” setting on the Power Curve it’s quite interesting (to me only of course) to see that a) my MLSS and CP are possibly very similar numbers and b) I’m nowhere near as fit as I was mid last year following SSBHV+.
So if this mythical rider stretched his W’ over 40 minutes (20000/(40x60)) it would add 8.3w to his CP for 208.3w expected best 40 minute power. And over 70 minutes (20000/(70x60)) , 4.8w for a 204.8w best 70 min power.
A hack like me might just say he has an FTP of about 206w. Then I’d make him do a 20 minute TT, where we would expect his W’ to give him (20000/(20X60)) 16.6w over his CP, for 216.6w.
Then just to check, we could multiply that by 0.95 to get an estimated FTP of 205.7
Is this starting to feel like a circular discussion yet? 
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