Chris Froome is currently leading the legendary Tour de France race, and wearing the famous yellow jersey.

So far, so good.

But the ace cyclist may have more challenges ahead than just the formidable mountain stages in the Pyrenees and the Alps. Because, according to Froome's fellow members in British-based Team Sky, someone may have hacked into his training data files in an attempt to suggest that he has been using banned performance-enhancing drugs.

As The Telegraph reports, Team Sky general manager Sir Dave Brailsford has ordered an investigation into how confidential data on Froome began to appear on social media sites.

The news follows the posting on Twitter of a video on Monday night, showing Froome's historic climb of Mont Venoux in 2013, overlaid with training data such as Froome's heart rate, cadence, power and speed.

The video was subsequently removed, but other posts online claimed that performance data from the Mount Venoux climb revealed that Froome accelerated from 19kph to 31kph in a five-second burst on a steep gradient.

Brailsford revealed that he suspected hackers may have stolen Froome's data, when asked whether he was anticipating the seemingly inevitable questions about doping if Froome performed well in the mountains in the next couple of weeks.

"It’s part of the game, isn’t it? If he does well, the rest of the Tour it's 'How do you know he’s not doping?'"

"The question of how to prove a negative is always going to be a difficult one. We think someone has hacked into our training data and got Chris’s files, so we’ve got some legal guys on the case there."

"I would never mention a name [but] ethically and morally, if you are going to accuse someone of doping, then don’t cheat [steal]"

Chris FroomeFor his part, before the Tour de France, Froome has chastised those who attempt to interpret performance data, claiming it is meaningless without context:

"It can’t paint the full picture. If the UCI [cycling's world governing body] want to collect power data and a way of explaining what’s humanly possible or not without doping, then I would be very happy. But to release it into the world for people to rip apart and say, 'On this 15-minute section he was too fast' ... you don’t get wind speed, temperature, how hard you’ve ridden, all those variable factors."

The world of professional cycling, of course, has been dogged with drug cheats for years - most famously Lance Armstrong who was stripped of seven Tour de France titles in 2012.

And, perhaps surprisingly to some, it's not entirely unheard of for the Tour de France to find itself embroiled in a hacking scandal.

In 2006, American cyclist Floyd Landis won the competition, but subsequently had the title stripped off him after a laboratory found unusually high levels of testosterone in his body.

Things took an unexpected twist, however, when the Paris-based laboratory found a Trojan horse on its computer system that allegedly allowed hackers to steal data (some of which was reportedly tampered with to suggest samples had not been handled properly). Lab director Pierre Bordry claimed that the hack was an attempt to discredit the tests done on Floyd Landis's samples.

A French court later convicted Landis, giving him a 12 month suspended sentence, although he was never directly linked to Alain Quiros, the hacker who admitted breaking into the lab's computers and was sentenced to six months in prison.

It's not just cyclists who have become embroiled in hacking, of course. Last month I reported how the St. Louis Cardinals, one the United States’s top major league baseball teams, was being investigated for allegedly hacking into the computer systems of sporting rivals.

Has Chris Froome been cheating by using performance-enhancing drugs ? I wouldn't have a clue, but it seems unfair to besmirch his character and achievements without compelling evidence. That evidence is best gathered, I suspect, by the authorities rather than amateur sleuths on social media.

Has Team Sky been hacked? It's hard to say for certain - but it certainly sounds as if sensitive information has fallen into unauthorised hands via one route or another. As the team's chief, Sir Dave Brailsford would be wise to look long and hard at what protections are in place, and no doubt there are lessons to be learnt.