Mike Sherwin likes the famous yellow Livestrong bracelet so much, occasionally he wears two.

It might also be a gentle reminder to his colleagues at the Lance Armstrong Foundation that initially, he was the only person among them who thought the distinctive yellow wristband was a good idea.

The wristband has become a worldwide fashion accessory and is effectively the symbol of the foundation, which started in 1997 as Armstrong was recovering from cancer.

Foundation chief executive Doug Ulman, himself a cancer survivor, remembers well the meeting where sporting good giant Nike initially pitched the wristband idea.

Armstrong was among the majority who first screwed up their noses. There's one board member in the foundation (Sherwin), one person, who was on the call, Ulman said.

Afterwards, he called me and said 'you're going to need more than six million'... smart man.

Sometimes he wears two.

The wristbands swiftly grew in popularity through 2004 and several other charities have copied the idea.

The overall leader of the Tour de France, cycling's most famous race, wears the famous yellow jersey and it has become Armstrong's signature colour. He won the first of his record seven Tour titles in 1999, just three years after nearly dying from testicular cancer.

This week, Armstrong is making his much-anticipated sporting comeback at Adelaide's Tour Down Under after three years of retirement.

He says the major reason for the comeback is to help promote the foundation's global cancer initiative.

Many of Armstrong's confidantes were shocked or concerned when the 37-year-old initially told them the comeback would happen.

But Ulman was ecstatic, because he knew the attendant publicity would be gold for the foundation.

And so it has proved - Armstrong officially launched the global campaign on Monday, the day before the Tour Down Under started.

He met with Prime Minister Kevin Rudd twice on Tuesday and the Australian Government has pledged attendance at the foundation's global summit later this year.

It's a once-in-a-lifetime opportunity - for the disease and for people around the world who are needing inspiration and hope and empowerment, you couldn't ask for a better platform to tell that story, Ulman said.

When he said he was coming back and he said 'don't you think that would help our global campaign?', I said it will absolutely help.

I will never forget where I was sitting when he called me.

The foundation has raised about $US250 million over the last 12 years and its main goals are raising community awareness about the disease, along with advocacy for those suffering from the disease.

The bike that Armstrong is riding this week features two numbers painted on the frame - 1274, the number of days between retirement and comeback, and 27.5.

The second number is for the estimated 27.5 million people globally who have died from cancer in that time.

Everybody deserves to have a high quality of life, Ulman says.

Every single person... deserves to get treated.

While the foundation does not aim to be biggest non-profit organisation associated with the disease, Ulman admits its goal is lofty.

Speaking at Monday's launch, Ulman declared we aim to eradicate all death and suffering due to cancer.

For a man as driven as Armstrong, nothing less would do.