Chris Froome data suggests weight loss led to Tour de France transformation

Chris Froome

Data released on the double Tour de France winner Chris Froome in answer to insinuations of doping during this year’s race showed that his success can be put down to a massive loss in weight, helping to explain his improvement from also-ran to Tour de France winner.

Froome hit the scales at 75.6kg in 2007 and slimmed down to a racing trim of 67kg in 2015, while maintaining a similar sustained power output.

During this year’s Tour, Froome faced almost daily questioning over his ethics, while he and his Team Sky team-mates had an occasionally hostile reception from the roadside, with fans spitting at them while on one occasion urine was thrown over their Kenya-born leader. In response he and Team Sky released a limited amount of data during the race, while Froome stated he would undergo independent physiological testing to prove his probity.

The data from tests carried out on Froome in August at the GSK Human Performance laboratory in London are due to be published on Friday in an interview with Esquire magazine, and they appear in conjunction with the results of physiological tests that Froome underwent in 2007 at the Swiss Olympic Medical Centre in Lausanne, meaning a direct comparison can be made between the 22-year-old Froome, who was clearly a rough diamond in cycling terms, and the winner of the Tour de France eight years later.

What is clear is that Froome increased his power to weight ratio by around 10%, enough to make a massive difference while climbing the Tour’s mountains, and to give a smaller but still significant improvement while racing on the flat, due to the reduced weight he would be shifting each time he accelerated. Froome’s power-weight at sustained effort in 2015 is estimated at just over six watts per kilogramme of body weight.

That represents a huge increase on the 5.56 he registered in 2007, but is still far short of the seven watts per kilo estimated by a French television during the Tour de France this year, in a report which prompted Sir Dave Brailsford’s Team Sky squad to overturn their previous policy of treating rider data as confidential, putting Froome’s statistics from 14 July on the La Pierre Saint Martin climb into the public domain at a press conference on the rest day during the final week of the Tour.

The GSK tests released in Esquire also measured Froome’s VO2 Max, his ability to absorb oxygen through the lungs, which is widely taken as a measure of absolute athletic ability; it was measured at 84.6 litres per kilo of body weight, or an estimated 88.6 for his Tour de France weight of 67kg as he had put on weight before doing the GSK tests. That is high, but not off the scale, given that world class team track riders were registering similar figures 15 years ago.

Froome is only one of a number of top cyclists to release data from Grand Tours this year. Most notably the Dutchman Tom Dumoulin made public many of his figures after his surprising ride to second place in the Vuelta à España in September. Froome’s move was intended to quash the doubting voices – primarily in French media but also across the internet – who have questioned the ethics of his two Tour de France victories, this year and in 2013.

Echoing the sentiments of the Team Sky head Sir Dave Brailsford, Sir Bradley Wiggins said on Thursday that he feared Froome’s action in releasing his data might not be enough to silence the sceptics. “It’s what people have called for and Chris has done it, so hats off to him,” Wiggins – who faced similar questioning when he won the Tour in 2012 – told BBC Radio 5 Live. “I’m sure it is not something for them to live and die by, or if it will change anything. It is a small step maybe.”

The full article appears in the January issue of Esquire on sale 8 December, also available as a digital edition

Powered by Guardian.co.ukThis article was written by William Fotheringham, for The Guardian on Friday 4th December 2015 00.01 Europe/London

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