Today, Flint from Zwift posted a notice on the forum to inform racers that “ZwiftPower category has been replaced, and is now calculated by our Category Enforcement metrics.” Read the full post >
What does this all mean? Let’s dig in and find out…
A Short ZwiftPower History
ZwiftPower was launched in 2016 as a collaboration between Glen Knight and James Hodges. Glenn handled the hardware side, originally running the ZwiftPower servers out of his garage. James was the programmer. Both poured countless hours into the site. It quickly became the place where Zwift race results lived, since Zwift wasn’t controlling who joined which category or doing any post-processing of results.
Simply put: if you didn’t have a ZwiftPower account, you weren’t a serious Zwift racer. And as a serious racer, you knew the breakdown of ZwiftPower’s FTP-based categories, which quickly became the standard for race categorization on Zwift:
James and Glen signed a contract with Zwift in October 2018, assigning all ZwiftPower-related intellectual property to Zwift. (This contract included terms outlining Zwift’s financial support of the site, but those terms have never been disclosed.)
Then in July 2020, Zwift took over the hosting and management of ZwiftPower. Zwift said this was done to improve product stability. It also allowed for more clear-cut GDPR compliance, since Zwifter’s data would no longer be shipping off to a third-party site.
ZwiftPower hasn’t evolved much since Zwift took it over, but this isn’t surprising. Zwift has been investing in its own systems, with the goal of moving away from ZwiftPower at some point. So we haven’t seen any significant upgrades to the ZwiftPower site since July 2020.
ZwiftPower did a good job of handling post-race processing of results, but there was no way to stop riders from signing up for the wrong category and blowing up a race. (Example: a sandbagging A rider might get a DQ in the ZwiftPower results, but they’d already blown apart the C race!)
To solve this problem, Zwift started testing Category Enforcement in February 2022. The goal was to set a minimum race category based on a rider’s historic power numbers on Zwift, blocking riders from racing categories below their detected ability. And it worked! Today, approximately 2/3 of all race events on Zwift use Category Enforcement, as indicated by this icon in the Companion app:
But the world of Zwift categories has been confusing since February 2022, because ZwiftPower had an FTP-based categorization scheme separate from Category Enforcement’s zFTP+zMAP-based scheme. The categories overlap in a big way, but riders on the edge of categories (for instance, a low-end B or a high-end C) were often categorized one way by ZwiftPower, and another by Category Enforcement.
Today’s change (in theory) eliminates that confusion.
A Few Notes
- The category update on your ZwiftPower profile will not happen automatically. You have to either take part in an event or click the ‘Refresh profile’ option on your ZwiftPower profile to see the Category Enforcement information on your profile.
- A+ riders will still show in ZwiftPower, for legacy purposes. A+ riders will be anyone with a zFTP >4.6 w/kg AND >300w.
- Event organizers should note that by default ZwiftPower will no longer Upgrade or DQ riders based on their category or W/Kg limits. (This shouldn’t be needed anymore, as long as your event is using Category Enforcement to restrict signups on the front end.) Event organizers will have to configure this option explicitly in ZwiftPower on a per-event basis if they wish to continue using the legacy system. This change won’t affect events already in ZwiftPower. Only future events being picked up will have those enforcement options turned off by default.
- WTRL’s popular Thursday TTT used ZwiftPower’s categories, but those will now shift to Category Enforcement. See WTRL’s post on this >
Wrapping It Up
This is a smart move by Zwift since it simplifies the Zwift racing landscape by creating one category scheme to rule them all.
Additionally, this change will increase fairness in Zwift racing. The metrics used by Category Enforcement are simply more robust than ZwiftPower’s legacy FTP-based categories, which were easy to “game” by keeping one’s 20-minute power below certain thresholds.
Until results-based categorization arrives, a unified Category Enforcement structure is a significant upgrade from what Zwift racers have used in the past. Ride on!
Questions or Comments?