London: Two-time Tour de France winner Chris Froome has released independantly tested physiological data in an ongoing attempt to convince doubters his astonishing mountainside accelerations are 100 per cent clean of doping.
Kenyan-born Froome, 30, won the Tour de France in 2013 and 2015 and is as adept at the time-trial as he is peerless on the steepest slopes.
Cynicism in the cycling world after the Lance Armstrong and Festina scandals saw accusations fly and fingers pointed at Froome due to the manner in which he is able to leave his rivals behind on the slopes.
Team Sky leader Froome told Esquire UK magazine published on Thursday: "Questions do need to be asked. As long as the questions are fair, I`m happy to answer them.
"What gets my back up is when those questions turn into straightforward accusations.
"I know what I`ve done to get here. I`m the only one who can really say 100 per cent that I`m clean.
"I haven`t broken the rules. I haven`t cheated. I haven`t taken any secret substance that isn`t known of yet.
"I know my results will stand the test of time, that 10, 15 years down the line people won`t say, `Ah, so that was his secret.` There isn`t a secret."
Froome and Team Sky were both criticised during this year`s Tour when data, which appeared to show Froome`s power, cadence, and heart-rate values from his stage-winning ride on Mont Ventoux in the 2013 Tour, was posted online and later made into a video.
The rider was doused with urine by roadside fans and called a doper on his way to clinching a second Tour yellow jersey.
Froome then agreed to undergo independent testing, which took place at GlaxoSmithKline`s human performance laboratory in London in August.
Froome`s VO2 max - the maximum volume of oxygen that an athlete can use, measured in millilitres per kilogramme of body weight per minute (ml/kg/min) - was recorded as 84.6.
At his Tour-winning weight it would correlate to 88.2, according to Esquire.
The general population has a VO2 max of 35 to 40, with highly trained individuals in the 50s and 60s. A few athletes have been measured in the 90s, including three-time Tour winner Greg LeMond.
Phillip Bell, a senior sports scientist at GSK, told Esquire: "Froome`s values are close to what we believe are the upper limits for VO2 peak in humans."