Team Sky may release more Froome data

Chris Froome, in a bid to prove he is clean, has undergone testing and released results. To further satisfy sceptics, Team Sky are considering the release of his daily power data during the Tour de France.
Chris Froome, in a bid to prove he is clean, has undergone testing and released results. To further satisfy sceptics, Team Sky are considering the release of his daily power data during the Tour de France.PHOTO: REUTERS

LONDON • Team Sky are considering the release of Chris Froome's daily power data during the Tour de France as they brace themselves for renewed demands for full disclosure about his performances.

Despite the two-time Tour winner publishing his own physiological study on Friday, Sky know that it has created an appetite for more.

It was Froome's own wish to undergo independent testing that, along with the release of some 2007 physical data on Friday, was intended "to rebuild trust in the sport I love".

What was made available appeared to show that Froome has always had an extraordinary physical capacity.

Weight loss, principally to help him climb better, had helped to turn his potential into Tour victories in 2013 and 2015.

The tests were carried out at the GlaxoSmithKline Human Performance Lab (GSK HPL) in London in August as Froome sought to push back against some of the rumours and allegations of cheating during a tempestuous race this summer.

He hoped he would "satisfy some of the questions asked".

But, for some sceptics, no amount of data can be enough unless he releases every bit of power data from races and training, all information from the biological passport that tests for any suspicious fluctuations, and even his diet to explain how he holds his weight at 67kg (or 9.8 per cent body fat) - compared to 75.6kg (16.9 per cent) in 2007.

"There's been a growing move for transparency, and that's what we're trying to embrace," Team Sky team principal Dave Brailsford said on Friday.

"We want to take a role in this to show you can win the biggest bike races clean."

At the same time, Sky insist that releasing too much information would undermine their chances and assist rival teams who have invested far less time and resources in being at the cutting edge in training programmes and dietary needs.

The main indicator that Froome has always had the capacity of a Tour contender is the VO2 max, which is the maximum rate of oxygen consumption.

A senior scientist at GSK HPL, Dr Phillip Bell, had described Froome's VO2 max values as being "close to what we believe are the upper limitations for humans".

But some sceptics will not be silenced. And Brailsford argued that many of those from the worst of the doping era simply cannot understand the world has moved on.

"There are guys who rode and their way to get faster on a bike was to dope," he said.

"When they now see someone going fast on a bike, it's hard for them to compute how to do it without doping."


Key indicators on the bike


What it is: The maximum volume (V) of oxygen (O2) absorbed through the lungs into the bloodstream.

How it is measured: Millilitres of oxygen per kilogram of body mass per minute.

Why this matters: Oxygen is the fuel used by the muscles so VO2 max is an important indicator of an endurance athlete's potential.

Because it is weight-dependent, it can be increased by weight loss.

EPO, the banned drug, also boosts VO2 max by increasing the number of oxygen-carrying red blood cells.

How Chris Froome rates: At his Tour de France body weight of 67kg, his VO2 max is 88.2 - high even for professional cyclists, but not unheard of among Tour de France winners.

Studies have shown that an average untrained male would have a VO2 max of 36-52 while elite male athletes would have over 60.




What it is: The average energy transferred to the bike - a cyclist's equivalent of horsepower.

How it is measured: Watts, a measure of power, per kilogram of body mass (w/kg).

Why this matters: The more power a cyclist puts out, the faster he can go. But because speed is also limited by weight (among other things), cyclists aim to improve their watts-per-kilogram, or power-to-weight ratio.

How Froome rates: Over a 20 to 40-minute effort (approximately the length of an Alpine climb), he can generate an average output of 419 watts.

At his racing weight of 67kg, that equates to 6.25 w/kg.

An unfit man might manage 1.8 w/kg. A top amateur rider would be pleased with 5.5 w/kg.


What they are: The number of mature and immature red blood cells, the body's oxygen carriers.

How they are measured: Mature red blood cells contain haemoglobin. Immature (new) red blood cells are called reticulocytes. The so-called "off-score" is a ratio of haemoglobin to reticulocytes.

Why this matters: When athletes are blood doping, they are trying to boost their number of red blood cells and thus their oxygen- carrying capacity.

Doping therefore increases the number of reticulocytes.

This increase will show up in a blood test, but only if the athlete's normal blood values are known.

How Froome rates: On July 13, his haemoglobin was 15.3 grams per litre and 0.72 per cent of his red blood cells were immature.

These figures are nearly meaningless without knowing Froome's normal scores but a normal adult range for reticulocytes is 0.5 to 2.5 per cent.


A version of this article appeared in the print edition of The Sunday Times on December 06, 2015, with the headline 'Team Sky may release more Froome data'. Subscribe