Tour de France: Sad end for Armstrong who rides into sunset as 'tourist on a bike'

Half an hour before Lance Armstrong and eight other breakaway riders reached the stage finish at Pau on Tuesday, the American eased back to his team car. When his manager asked him how he was feeling, Armstrong simply replied, "I'm tired". The 38-year-old Texan did not need to say anything more to admit that he would not be able to battle for the stage win – he finished sixth – just as for two long weeks he has not been able to compete for any of the other mountain stages, or indeed for a final Tour de France win.

For a rider as innately – some might say unhealthily – ambitious as Armstrong, this year's Tour must have been a huge disappointment. Expectations were high, justifiably so. He was third last year but going into the race this time the American's form looked stronger and in his RadioShack team there was no division of loyalties like that between himself and his then team-mate Alberto Contador in 2009. He rode brilliantly in the first week in this Tour and the prospect of him finishing his last race in yellow, even at his age, seemed a real possibility.

But two crashes in a single Alpine stage and the injuries he suffered as a result poleaxed Armstrong. When he crossed the line at the end of the eighth stage in Morzine-Avoriaz nearly 12 minutes down, the first thing he told reporters was "my Tour is over".

With those four words the myth of "Armstrong the invincible" went up in smoke: the semi-official Tour newspaper L'Equipe, that once described Armstrong as "an all-conquering being from another planet", scathingly said he was a "tourist on a bike".

Since the Alps, the American has barely been a factor in the race, with Tuesday's break the exception that proved the rule. There were high hopes that he would be back in the action for yesterday's stage up the Col du Tourmalet: it didn't happen.

Two days before Paris, with his chances of a final stage win virtually zero, Armstrong's Tour de France record can be summed up. Seven overall victories and 24 stage wins add up to a domination of the event without precedent and make him an athlete who cannot fail to be a reference point for all sport.

Aggressive, charismatic, articulate and hugely talented, Armstrong has been impossible to ignore. But long-term, the benefits of his seven-year reign have been uneven.

On the plus side, Armstrong has pioneered everything from revolutionary new pedalling styles – the so-called "windmill", pedalling low gears at high speeds – to detailed reconnaissance of every mountain stage, now de rigueur for every major contender.

But unlike when America's first Tour winner Greg LeMond was regularly finishing first in Paris at the end of the 1980s and demanding vast salaries in return for himself and his team-mates, there has been no corresponding hike in wages across the board. It also goes without saying that the doping allegations that have dogged Armstrong have done cycling no favours, though he has always stenuously denied the allegations.

Commercially, the consequences are equally mixed, although the American's biggest impact unsurprisingly, has been in the United States. But only briefly. "If anybody was going to make cycling mainstream in America, it would have been Lance," says Andy Hood, the European correspondent of VeloNews, the US's best-selling magazine on the sport. "But that didn't happen. As soon as he [first] retired [in 2005], coverage in the States sank back to pre-1999 levels. It was all about Lance and the media interest in Lance was always partly because of his cancer backstory."

But the effect of his run of wins from 1999 to 2005 can still be felt. This month there are four American teams in the race, whereas for years there was only one – Armstrong's. If his RadioShack outfit has sucked in most of the media interest, there is more than enough left over for other businesses to want to be in on the act.

Curiously, his popularity has rocketed, even in France where he was once voted the country's least favourite athlete, since he stopped winning the Tour. Both last year and this year he has been the rider to receive the most fan mail on the Tour.

Part of this can be put down to Armstrong's impressively organised publicity machine for his Livestrong foundation, created to promote the fight against cancer, during the Tour. Around four dozen activists start their day at the Tour selling Livestrong bracelets, and later stencil what they call "words of hope" – short, upbeat messages about cancer and Armstrong – on the stage route. The money raised goes to local cancer charities, but at the same time the publicity raises Armstrong's profile and strengthens his association with the race.

The question of his long-term reputation is unlikely to be settled for some time, if only because the legal battles over the latest series of doping allegations made by former team-mate Floyd Landis are just starting to hot up. The latest instalment was the announcement that another former US Postal rider, Tyler Hamilton, had been subpoenaed by a federal investigation. Armstrong has never tested positive for banned substances and has dismissed the Landis allegations.

Ultimately, was Armstrong right to come back to the sport when, as Britain's Chris Boardman once said, he had nothing left to prove? With hindsight, as he heads towards Paris as just another rider, it is easy – too easy – to write off his return as unnecessary. But it was never that simple.

Had Armstrong not crashed in the Alps, this year's Tour could have been a final spectacular episode from an athlete who has – for better or for worse – gone beyond his sport in a way no cyclist ever did before. And if bad luck and accidents have meant Armstrong has over-reached himself this year, the American's sporting legacy – whatever it finally is – will not be changed by that. He has done too much in cycling, and sport, already.