i’d like a 300w ftp, or even a 290w ftp. it’s probably never happening though. the grass is always greener, right?
O yes, and I want to be a 80kg lightweight racer 
. (never gonna happen 
)
‘legitimate Bs’ is my new favourite phrase.
The system has changed. Some Bs have done full FTP test efforts (maybe a 16km TT), 3 times in 90 days, and can say that the old system had a true view of their FTP. Most haven’t. The new system may use CP instead of FTP, but the main thing is that it will get that value very accurate for almost every rider from fewer rides, so a lot of riders that will have moved up have done so simply as a result of a huge increase in accuracy.
In the new system, there is no such thing as a legitimate B that can only enter the A pen. In the old system, there were two valid arguments which made things extremely confusing:
-
they are 100% legitimate if they enter the pen ZP gives them
-
they are only legitimate if they enter the pen of their real FTP, regardless of the category ZP has given them
Things have actually become clearer cut, not muddier.
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the new system isn’t even working yet. cyrus would be filtered into B since his 5 min is below 5.4wkg and his CP is sub 250w if it was correctly working. he’s not hiding his numbers. people are giving him sh*t for no good reason, i hate that crap.
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You are right… I show my real numbers, my 20 minutes power is true as it was obtained on the epic kom trying to follow you, with a maximal effort for me, and I got exactly the same numbers on the mont ventoux irl last year.
And under the old rules i was a legitimate B… being a B doesn’t mean anything else than being between the category limits. That’s why I don’t really give a… about my category, I will be where they tell me to go.
But I won’t cruise or sandbag, I even tried attacking some strong opponents like coco on the flat, because I don’t like waiting for things to happen.
By the way that’s why I hate double draft : you can only wait for the end sprint with double draft.
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Well, no. There was no watt floor in the first iteration of the new system, so he was correctly placed. That wasn’t an oversight, it was deliberate. We advised that there should be one so they are adding it in, but there is a very strong argument that in the future it should be lowered.
Regardless, no bugs here that I have seen yet.
well whatever number you arrive at, as long as you understand that there has to be one. putting men aside, women and juniors can’t really participate meaningfully without it
Just a heads up (not a bye Felicia moment, I don’t really care for that) - that I’m bowing out of zwift and the forum for a few months. It’s taking too much of my time and effort when the community is treated with as much disdain as it is, and there are bigger things going on in the world tbh for me to get so annoyed with something so insignificant.
Hopefully I’ve explained throughout all the posts enough regarding how this new system works - it’s truly a big step forward, even if they are still completely out of touch with what is needed from a long term perspective, and even how to appropriately communicate the short term system to their user base. #FreeLuciano.
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Unless someone organizes women and junior race events.
Well, this is shite.
Thanks for the part you’ve played, it’s much appreciated by me and I suspect very many.
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RGT is it?
Don’t blame you, this forum has been a clusterfunk at times the last few months, and especially in recent days. Cheers for all your good work and patience - is much appreciated.
Sorry to hear James.
You’ve been a fantastic voice for change.
Sheit! How in the world are we going to get to 4k posts on the Anti-sandbagging thread without you to push things along, James? Your contribution will be missed for sure. We all hope to see you back here sooner rather than later.
i dont blame you. anyway regarding CP, i do think the system is fundamentally sound, details aside.
Stay safe and stay well. You will be missed by many. As others have said, great progress has been made but sadly a little too late. Like you said, far more important things to worry about, plus other platforms are certainly making far more progress. I know I’m checking them out after the recent tests and no doubt others will as well
We may not have always seen eye to eye on the best way to approach things but regardless your efforts are appreciated.
What i would say, if you enjoy doing something dont stop doing it - Take a back seat, block the forum for a few weeks but if you enjoy looking after your team and riding keep doing that.
Its your enjoyment, dont let outside forces change that,
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Is Critical Power (and the additional MAP component) really a good metric for identifying who should be moved up to the next category? I have always found CP calculations to be very sensitive to the quality of the best efforts included. Especially something like the 3 point test in the Highnorth spreadsheet referenced earlier in the thread.
Examples using the 3-point test on the Highnorth spreadsheet - for a 70kg C@3.12w/kg 95% of 20min
with the same 10 min and 20 min best efforts and a variety of different 3 min best efforts. (I don’t think any of these power numbers are outside of the bounds of possible riders)
Person #1 - C Cat
320w for 3 min (4.57w/kg)
250w for 10 min (3.57w/kg)
230w for 20 min (3.29w/kg) gives
CP=216w (3.10w/kg) W’=18.7KJ and 5 min Power of 284w (3.98w/kg)
Let’s change that 3 min number to someone more punchy and send CP down and the best calculated 5 min power up.
Person #2 - C Cat
335w for 3 min (4.78w/kg)
250w for 10 min (3.57w/kg)
230w for 20 min (3.29w/kg) gives
CP=212w (3.03w/kg) W’=22.1KJ and 5 min Power of 286w (4.09w/kg)
Add 5 more watts to the 3 min best and they have possibly tripped the MAP trigger to the next category
Person #3 - B Cat
340w for 3 min (4.85w/kg)
250w for 10 min (3.57w/kg)
230w for 20 min (3.29w/kg) gives
CP=211w (3.01w/kg) W’=23.2KJ and 5 min Power of 286w (4.12w/kg)
Take away some watts in 3 min power for a less punchy rider
Person #4 - C Cat
305w for 3 min (4.36w/kg)
250w for 10 min (3.57w/kg)
230w for 20 min (3.29w/kg) gives
CP=221w (3.14w/kg) W’=15.3KJ and 5 min Power of 272w (3.88w/kg)
Take away even more watts from 3 min power and you get someone who is catted up (97% goodness of fit, so certainly an outlier, but not an exceptional outlier)
Person #5 - B Cat
290w for 3 min (4.14w/kg)
250w for 10 min (3.57w/kg)
230w for 20 min (3.29w/kg) gives
CP=225w (3.21w/kg) W’=12.0KJ and 5 min Power of 264w (3.78w/kg)
Here, the riders who have been moved into another category are the anaerobically strongest (#3, by MAP) and anaerobically weakest (#5, by a CP above 95% of 20 min). To me it doesn’t really make sense to create a system where an anaerobically weaker rider should be moved up categories before a rider with the same 20 min power like Person #2. I know who I would bet on for most Zwift races. And, this is not even taking into account raw wattage ceilings for lighter riders.
Now the CP and W’ numbers do suggest that Person #5 might be stronger in longer races like a race up Ventoux or a 40k TT where they can leverage their better CP by riding steady and not deplete their smaller reserve of W’ compared to Person #3, but very few Zwift races are long and steady.
One simple fix to this model might be to never let CP in the Category calculation be higher than 95% of 20 min power. At least that makes sense for the edge case where a lower 3 min power moves someone up you would not expect.
Of course, this is probably not the way Zwift is calculating CP, but for most CP calcs I have seen, Critical Power can be higher than 95% of 20 min power for well developed aerobic riders. Those are the exact people that should not be moved up categories if the goal is to move up the riders who too easily win races with the current Category system.
3 Likes
I have now done 2 enforcement races and as I have been switched cat by the algorithm between the 2 races, I will share my experiences here.
The first was way back at the start of the week in enforcement version beta 2 (AND-OR bugfix), where, as a 53-54kg female with a CP of between 185-195W (depending what formula is used), I was in B pen on the Paris loops. I basically clung to the large second(ish) grupetto, doing fine on the hill but of course coming second to last in my group on the final sprint. Someone said that double draft is on for these races so maybe I wouldn’t cling on so well in all races. The pack pace was hard for the first lap and medium hard thereafter.
Then today, with enforcement algorithm version 3 (watt floor implemented) I was able to ride in C, for racing around 2 laps of Ocean cliff side. Several interesting things about this race.
Firstly, someone complained at the start there was a sandbagger, which precipitated me trying to explain the enforcement system in the chat! I too thought there could be no sandbaggers anymore. But the “sandbagger” won! I think that makes him worth looking in to: ZwiftPower - Login Other racers should not a priori be able to predict the winner…
The pack pace on the flat was easier than in the B race. Up the cliffside I could hang with the front group, but couldn’t break off the front. It’s a fairly punchy climb after all. On the downs I had to pedal - sometimes quite hard - to stay in touch. There was another woman about my weight in the race and I seemed a little quicker than her first time up the cliffside, and she a little quicker than me second time. But there was also a male of the same weight (53kg) and he did a big break away on lap 2 and got 30s up the road before the following group got our act together and … we did chase him down.
At the finish someone went long off the front up the ramp out of the tunnel and the front group jumped hard and dropped me and the other woman completely in the dust… so we finished 10th and 11th! I did over 300W at that point, but it was no where near enough to hang on!
The 53kg guy ended up finishing second in the sprint behind the curious “sandbagger” (who may not be human? orange jersey on steel bike with no HR).
So, in short, it was fine, and I think this latest version is a reasonable mirror of the old cat system with some significant improvements. My problems are really just the same as ever problem of mixed races - they make me feel like we women are a different species! Women’s B cat racing - where I spend more time - makes a lot more sense!
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i just tested it by putting my own numbers in and my CP rises when i lower my 3 min wattage and leave my 20 min as it is, i’m presuming the algorithm thinks i’m more aerobically developed relative to my actual ability if my power curve is flatter. i’m not using the highnorth spreadsheet because this thing doesn’t have excel on it, i just went to a 2 curve calc from the front page of google
396w 3min
270w cp20
CP 248
345w 3min (artificially lowered)
270w cp20
CP 257
is it punishing riders who have a flatter power curve?
i dont use CP in my training so i don’t fully understand the system, but this seems super weird to me.
i understand enough that the MAP component is designed to put a lid on it to some extent (for sure, i am in A regardless of my CP, though i wonder if that would still be true if i did not intentionally do a lot of max testing at sub 10min intervals on zwift), but given that zwift races already typically are in favour of those with an exceptionally strong minute, isn’t this just just going to punish people with a low anaerobic capacity even more? i think double draft is hiding some gaping holes here
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We’d also noticed this. It may seem initially counterintuitive but it’s natural enough that increasing your max power on a short time interval can tend to steepen the curve and therefore actually drop the RHS of the fitted power curve where it’s extrapolated beyond the longer time interval data point.
The problem is not so much in the CP calculation but rather in thinking that CP has any direct relevance to zwift racing. It just doesn’t. Its only relevance is indirectly, in what it generally means (but rather approximately) for shorter-term efforts. I think I mentioned I did about 3.1 for my B cat test race a couple of days ago - and a couple of guys who beat me were lower than that. I hardly pedalled a single stroke at threshold, it was either Z1/2 or flat out. The race was entirely decided on the two short climbs and slightly longer drag to the finish (Richmond UCI). Finish order was much more highly correlated with 1 min power than 20 min.
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