On Tuesday’s Tour de France rest day, Team Sky finally relented to the mounting pressure and released race leader Chris Froome’s performance data from his Stage 10 victory, on which he crushed his closest rivals on the first major climb of the Tour to take a commanding lead.
Since that day, he’s been in the eye of a media storm of suspicion surrounding his performance, had urine tossed on him, been called a cheater and doper, and meanwhile extended his lead to something close to insurmountable.
The data were revealed for the 41:30 of the main portion of the climb. Sky head coach Tim Kerrison went over the numbers:
“For that 41:30, Chris had an average power of 414 watts, which gives a 1602 VAM [“average ascent speed,” usually in meters per hour]. We know power Osymetric chainrings (used by Froome) over estimate power by about 6 per cent. That’s why it has to be considered when interpreting Chris’ power. With his weight hovering around 67.5kg that gives a correct power of 5.78 watts per kilo.
“Chris had a gearing of 52×39 and 11×28, which allows a lowest gear of 39×28 and allows for the high cadence that he does. He averaged 97rpm. His average heart rate was 158. His max heart rate was 174. For Chris that equals his highest heart rate in a Grand Tour, certainly in last few Grand Tours he’s done….” Here’s the Cycling News story of the data release.
Greg LeMond weighed in on the issue before the release of Froome’s data, commenting on mathematically assumed power numbers, saying: “Can people do what Chris did on the first mountain stage? I think it was 6.1 watts per kilo [Sky reported 5.78], which I think that’s within the realm of human performance.”
LeMond and others have referenced 7+ watts per kilo numbers recorded during the recent doping era as the “magic number” that is, in LeMond’s words, beyond “the realm of human performance.” In short, LeMond believes there’s nothing amiss about Froome’s performance or numbers. You can read his Cycling News commentshere.