What race category ?


(Neil Bell) #1

Never tried races before on Zwift but would like to give it a go.

Are the race category watts/kg bands based on FTP? My FTP is almost exactly 4w/kg but I wouldn’t average that much for an hour in a race situation. That said, I’d slightly exceed 4w/kg average on a 20min steady climb such as on the new Innsbruck course. I’m light at 63kg. Should I join the B category?

How does the disqualification work, is it that you are not allowed to average more than your FTP or a time-corrected equivalent, or is some other calculation used?

I’d probably play to my strengths and enter a race with a good amount of climbing, e.g. on the Innsbruck WC course.


(Nigel Doyle) #2

The categories are based on what your FTP divided by your weight is i.e. watts per kg. They aren’t based on what watts per kg you might do during the race. That said if you enter as a B grade then exceed the power ratio you’ll usually be automatically upgraded to the A grade at zwiftpower.com Are you registered at zwiftpower.com? You need to be for your results to count.

I’m currently about 3.98 w/kg so enter as a B grade. I can hold over 4 w/kg in short races e.g. 10km as can many other B grade riders. B grade is the correct grade for me. It’s important to enter the correct grade otherwise you’ll piss people off especially if you get upgraded. I think there’s some mechanism for repeat offenders who enter grades lower than they should be.


(Neil Bell) #3

Thanks - haven’t registered with zwiftpower.com yet but will do so.

FTP is your max sustainable power over an hour obviously, so I’m just wondering how they calculate if you have exceeded the ratio for shorter or longer races than an hour. People vary quite a bit in how FTP correlates with, say, their 20min power or their 2 hour power.

But I’m assuming that for a race that lasted exactly one hour you would be upgraded if you even slightly exceeded 4w/kg average for one hour?


(Nigel Doyle) #4

I don’t agree that your FTP is your sustainable power over 1 hour. Theoretically it might be but most people including myself can’t hold their FTP for an hour. It’s more a metric to give you a figure to determine % based workouts from. For the purposes of Zwift racing your FTP is generally considered your max 20 minute power x.95

The Facebook Zwiftracers group has discussed upgrading and the various criteria a few times. Join up and do a few searches. The short race scenario where people go over the w/kg limit has been covered I recall.

At the end of the day it’s just a game. There are people weight doping then people on the likes of the Tacx Vortex getting an extra free 50 watts because they can be very inaccurate even when calibrated.


(Gerrie Delport) #5

Zwift power look at your best 20min during a race and compare that to 95% of your ftp.


(Neil Bell) #6

<<I don’t agree that your FTP is your sustainable power over 1 hour. Theoretically it might be but most people including myself can’t hold their FTP for an hour.>>

FTP *by definition* is your maximum sustainable power over 1 hour - but absolute maximum at a completely constant output of course.


(Neil Bell) #7

<<For the purposes of Zwift racing your FTP is generally considered your max 20 minute power x.95>>

<<Zwift power look at your best 20min during a race and compare that to 95% of your ftp.>>

OK that’s fine and makes sense. So category B is for people below 4.21 w/kg over 20mins.


(Gerrie Delport) #8

But that 4.21w/kg is not calculated by deviding your ftp by weight, it is the average power during your 20min section of the test devided by weight.

A true Ftp test is a max effort over a hour but most of us can’t do a hour test on a regular base, so the 20min or 8 min or taper method was developed so you can guage your performance more frequently without to much stress.
http://www.hunterallenpowerblog.com/2013/01/what-is-ftp.html?m=1


(Neil Bell) #9

Yes, I know… :slight_smile:

It doesn’t matter. If Zwift racing uses that particular criterion for deciding when to upgrade people, then it’s not actually your FTP that determines what category you should be in, it’s your 20min power.

The best way to work out your category (from what I’ve read, I haven’t raced yet!) is to look at your 20min power.

The 4w/kg at FTP cut-off that is stated is best seen as a guide - if your FTP is 4w/kg then your 20min power might be around 4.21w/kg. But it’s the latter figure that matters.

Ironically this is the opposite of the usual situation where people are using their 20min power to estimate their 1 hour power (FTP). Here it seems we should use our 1 hour power to estimate our 20min power, because that’s what the cut-off is actually based on. But the irony is that most people’s 1 hour power is estimated from their 20min power to begin with… :wink:

Simply put, what I’m saying is that if the cut off is based on maximum sustained 20min power then it would be much better to define the race categories based on that rather than on FTP.


(Gerrie Delport) #10

It is just easier to use FTP, most people can’t even calculate w/kg form their FTP…LOL

 

It is just a easy to use system. Don’t over think it. Enter a race and see how it goes. 

 

The ultimate goal is to have a points system/ranking system. not w/kg

 


(Joe Daknis) #11

“It is just a easy to use system. Don’t over think it. Enter a race and see how it goes.”

Exactly.

If you enter a B race and perform better than expected or find the competition lacking, move up to A.  It’s not rocket science.