The cost of ensuring accuracy in cycling esports: Is it time for hardware manufacturers to adapt to the strict standards of Elite competition?
Originally reported on Cycling News!
Amid a racing season marred by multiple racer annulments, mid-series format changes, and ruleset amendments, Zwift has halted its elite five-race Zwift World Series, leaving trust in the platform’s flagship Zwift Games in doubt.
In an email sent to racers, Zwift announced the unprecedented decision to pause the Zwift World Series and will not go ahead with the series’ fourth race scheduled for December 5th.
Zwift’s Director of Racing, Sean Parry, explained the profound nature of the platform’s predicament, “This decision has been made after a thorough review, and it has been driven by our desire to uphold the reputation of our sport and protect the well-being of the athletes.”
At the heart of the issue are smart trainers and digital communication protocols, which manufacturers never intended to meet the intense demands or strict standards of elite cycling esports competition.
The industry is slow to adapt.
Athlete AnalytiX, an independent performance verification service headed by the former head of ZADA (Zwift Accuracy and Data Analysis) Bjoern Ossenbrink, contracted by Zwift for the 2024/25 elite season, detected the accuracy issues.
All elite cycling esports races require dual power meter recordings to ensure consistency by comparing readings from multiple sources, usually a crank or pedal-based power meter and the smart trainer. The hardware manufacturer’s proprietary algorithms estimate power, and each one does it differently.
A problem occurs when the dual recording curves show unacceptable differences, in the range of 7 to 10%, that vary under different race scenarios without specific definable causes or logical explanations from the manufacturers and auto-calibration protocols that introduce errors and the false perception of accuracy.
Parry summed it up, stating, “This season in the Zwift World Series, we have seen, and we continue to see, a much higher volume of issues with hardware accuracy than we ever have in the past. Unfortunately, this has resulted in many annulments, race to race uncertainty for athletes, and created considerable challenges for our performance verification team and commissaire. We understand and empathize with the strain that this has put on riders throughout the series, and this is not something we can allow to continue.”
Word of the problem initially went public before the series’ second race in early October. Athlete AnalytiX identified anomalies in power output for several riders, occurring exclusively during climbs (steep gradients at high power outputs) on the race route.
These discrepancies prevented the verification of their performances. Since all affected riders used the same trainer model, Zwift and Athlete AnalytiX initiated an investigation with the manufacturer to determine the cause, prompting this statement from the smart trainer manufacturer Wahoo.
“Under extreme conditions—specifically high absolute power on extended climbs at 100% trainer difficulty—power may drift slightly on KICKR V6 and MOVE only. We believe this to be an edge case that impacts only the most powerful indoor racing specialists. We are working on a bug fix, but in the interim, we advise elite riders to set trainer difficulty to 50%.”
That bug fix hasn’t arrived.
New Zealand’s Kate McCarthy used an Elite Justo smart trainer when Zwift annulled her dominant performance in the Zwift World Series second race. The Independent Commissaire absolved McCarthy of any intent to cheat, stating, “The rider experienced a hardware malfunction which led to a material difference between the trainer and power meter for the duration of the race.”
The court of public opinion felt otherwise, prompting McCarthy to fend off performance authenticity questions following her 2024 UCI Cycling Esports World Championship victory.
“I had a point to prove this week,” McCarthy made the post-race statement after riding a UCI standardized smart trainer in a live setting, dispelling doubts that plague the developing sport. The 2024 edition was the first contested on UCI-standardized smart trainers in front of a live audience. Zwift hosted the first three before the UCI awarded the World Championship tender to MyWhoosh in 2024 for the next three years.
The 2024 World Championship silver medalist, Brazil’s Gabi Guerra, used an Elite Justo 2 smart trainer when Zwift annulled her after winning Zwift World Series race 3 in a solo breakaway.
The Independent Commissaire’s report read, “The rider was riding a brand-new Elite Justo trainer that had undergone factory calibration. This was the first time the smart trainer was used in the Zwift World Series. Throughout the duration of the race, for reasons unknown, material and inconsistent variances between the smart trainer and the power meter occurred. This rider is not at fault, the performance cannot be verified.”
Several other male and female racers fell a similar fate and experienced significant stress and anguish due to ZWS annulments.
Despite this, the postponement decision has sparked consternation among racers, many of whom structure their competitive seasons around the Zwift World Series. Frustration is mounting as racers find themselves catching the most heat, forced into the position of defending their integrity amid ongoing challenges.
Zwift plans to reschedule the final two races of the elite season to follow the Zwift Games 2025 in March. This adjustment raises concerns, as qualification for the Games depends on performances in these concluding Zwift World Series events.
The situation is especially concerning to McCarthy, who, after losing points toward qualification due to the annulment, targeted the final two races of the Zwift World Series to gain a coveted entry into the Zwift Games.
“I have some concerns around what the pathway forward to the Zwift Games will now look like and how they will ensure that, too is fair, explains McCarthy. Being a rider impacted by the annulments, I was relying on the final two races to get a spot in the Zwift Games.”
Without a special amendment to the qualification criteria, annulled riders such as McCarthy will be punished twice for something outside of their control.
“To have our whole race season hung up like this is insane,” passionately exclaims elite racer Dean Cunningham, “but it shows how reliant we are on this hardware.”
Unfortunately, this is not a new problem anyone thinks will be realistically solved soon, and questions also surround the involvement of the sport’s world governing body, the Union Cycliste Internationale (UCI).
The UCI’s Head of Innovation and Esports at the time, Michael Rogers, in a January 2024 interview, told The Zommunique, “We are quite advanced in homologation of smart trainers. We are prepared to announce something within two to three months.”
Rogers alluded to the UCI’s collaboration with Purdue University’s Engineering department to create a smart trainer homologation program. Ten months later, the initiative isn’t implemented, forcing virtual platforms to face tough compromises.
“Given the events that have occurred,” states Zwift’s Parry, “we will also take this opportunity to revisit and update our ruleset for elite racing. Our emphasis remains on maintaining the highest levels of fairness possible but we would like to explore sanctions and remedies that are less severe than the current rules when athletes encounter unintentional infractions outside of their reasonable control.”
The racing community worries that the only viable solution might involve lowering verification standards to compensate for the industry’s slow adaptation. It could also lead to more restrictive and potentially costlier equipment requirements, adding to the already significant technological barriers to entry into the sport.
Parry urges that Zwift is taking steps to dissuade this, stating, “Whilst the equipment on the ZWS whitelist (approved hardware for elite competition) works extremely well for 99+% of indoor cyclists, the extreme demands that some elite racers place on hardware mean that there are edge cases that have emerged. We firmly believe these edge cases can be remedied by hardware manufacturers developing firmware updates.”
Ollie Jones, who rose to prominence by winning the 2018 Zwift Academy, has been a consistent force in cycling esports, representing New Zealand in every UCI Cycling Esports World Championship and securing a top-ten finish in 2024. As the current GC leader poised to claim the $3,000 Zwift World Series top prize, the pragmatic Kiwi remains optimistic, viewing this turn of events as an opportunity to drive positive change in the sport.
“I’m obviously disappointed for the postponement, “ shares Jones. “I was excited to defend my leader’s jersey over the last two rounds of the ZWS. On the other hand, as a rider who’s seen the highs and lows of this scene for 7 years now, I understand that as a remote sport, we don’t have anything without a strong mutual trust in the accuracy of the framework underlying an event. This includes everything from hardware manufacturers to the verification process. I am happy to see further progress implemented into that framework for future events and will be ready to defend my lead when the time presents itself.”
Zwift is postponing the ZWS to give riders and manufacturers the necessary time to better understand, diagnose, and resolve issues, ensuring greater certainty and confidence for athletes moving forward. For Zwift, perfect may be the enemy of good, and the risk of binning their only elite racing series could have irreparable repercussions for the platform and the sport.
Some racers applaud Zwift for taking action and making the difficult decision to progress the sport.
South Africa’s James Barnes, a prolific winner in Zwift elite racing and a top-twenty finisher at the 2024 UCI Cycling Esports World Championship, is keenly watching how this decision will shape virtual racing and impact his peers.
“I am glad they are addressing the equipment annulments that have been out of the rider’s control, taking action, and rewriting the rules and regulations relating to such incidents. It’s a shame it caused huge stress for riders at the mercy of the hardware.”
The sentiment highlights a core issue: hardware manufacturers, virtual cycling platforms, and governing bodies must collaborate to establish universal standards of accuracy and fairness tailored specifically to cycling esports.
“Joint collaboration between Zwift, hardware manufacturers, and riders during this time will ensure that we can all move fairness in the sport forward together,” urges Parry.
Until then, surrendering to the inability to effectively verify athlete performance due to hardware inadequacies casts a poor light on a sport striving to establish itself as a unique cycling discipline. It comes at a crucial time, with the International Olympic Committee’s Executive Board soon deciding which sports will feature in the Olympic Esports Games.
It’s time for the hardware manufacturers to catch up.
Semi-retired after more than 20 years as the owner and director of a private Orthopedic Physical Therapy practice, Chris now enjoys the freedom to dedicate himself to his passions—virtual cycling and writing.
Driven to give back to the sport that has enriched his life with countless experiences and relationships, he founded a non-profit organization, TheDIRTDadFund. In the summer of 2022, he rode 3,900 miles from San Francisco to his “Gain Cave” on Long Island, New York, raising support for his charity.
His passion for cycling shines through in his writing, which has been featured in prominent publications like Cycling Weekly, Cycling News, road.cc, Zwift Insider, Endurance.biz, and Bicycling. In 2024, he was on-site in Abu Dhabi, covering the first live, in-person UCI Cycling Esports World Championship.
His contributions to cycling esports have not gone unnoticed, with his work cited in multiple research papers exploring this evolving discipline. He sits alongside esteemed esports scientists as a member of the Virtual Sports Research Network and contributes to groundbreaking research exploring the new frontier of virtual physical sport. Chris co-hosts The Virtual Velo Podcast, too.
Finally! I’ve been saying for ages that the manufacturers have been getting away with using +-1% claims, which is based on accuracy to ITSELF not other trainers/power meters from the same manufacturer let alone a standard. The spreading of “this trainer/power meter is more accurate because it’s +-1%” by the industry and reviewer’s who don’t race has led us to this point.
I had this same issue with DQ’s in DRS, and when I went dual power to pedals as well – there was a 20% difference between my KICKR Bike and the Favero’s. Random number generators! The eRacing is a farce, and the community of Wwift is toxic in its constant pointing to people supposedly cheating. I feel vindicated seeing this happen. Let me know when it gets sorted out, otherwise I will be outside or on Fulgaz.