Image caption "Crossing the line with my hands in the air" - Mark Cavendish helps promote his team sponsor Sky

World champion cyclist Mark Cavendish - who justifiably describes himself as "the fastest man on two wheels'"- has a strenuous summer ahead of him.

The 27-year-old defends the green jersey he won in the 2011 Tour de France, while also looking to win gold in the London 2012 cycling road race.

Before competing in the Olympics, he will have cycled some 3,500km (2,175 miles) in the Tour de France, which gets under way in Belgium on 30 June.

The Manxman is a winner of 20 stages in the last four Tours.

Six days after the end of the 99th staging of the Tour, he will then line up in London on 28 July for the Olympic road race, the climax of which ends in the Mall.

"It is not easy but it is possible," says the sprint specialist, speaking at a Sport Industry Group event in London.

"I am doing both for different reasons.

"There are some guys missing out the Tour de France to concentrate on the Olympics.

"But the Tour de France is the biggest cycling race in the world, commercially. For any sponsor putting money into cycling, the race is a big factor in any deal."

The BBC's current Sports Personality of the Year considers the French race the high point of his cycling season, but also points out that "the Olympic Games is a big thing to me, especially with it being held in my own country".

"I think I can do well in both," he says.

Sponsors

Last year he rode for the now defunct HTC-Highroad Team, and won the green jersey for most Tour de France race points, acquired for consistently high finishes in the Tour's 21 stages.

Image caption In 2011, Cavendish, racing for HTC-Highroad, won the Tour de France green jersey

The father-of-one now races for Team Sky, a Manchester-based UK team sponsored by the satellite broadcast firm.

He is the only cyclist ever to win the final stage of the Tour de France, along the Champs-Elysees in Paris, for three years in succession.

And he will be seeking other high-profile finishes in this summer's three-week-long race, for both sporting and commercial reasons.

"Fundamentally my job is to display the sponsor's logo as predominantly as possible, preferably crossing the line with my hands in the air," he says.

And he is clear about the important role business plays in keeping the sport on the road.

"It is a commercial thing - it is about displaying sponsors' logos," he says. "That is where the money comes from."

'Relaxed'

From a personal point he feels he has benefited from signing with the Wasserman sports agency last year.

"Two years ago I was commercially less valuable than I am now, but I was was doing more - it was affecting my cycling, and I could not train because of the [commercial] commitments I had," he recalls.

Image caption Cavendish has a sponsorship deal with Oakley sunglasses

"Everything is now so relaxed, and structured. My life is so much easier."

His two biggest commercial contracts, apart from his team's association with Sky, are with sportswear firm Nike and sunglasses firm Oakley.

"I have to believe in a product before I go with it," he says. "I have had things brought to me and I am not interested in them.

"I have been offered more from other brands, but those two had faith in me and provided me with products when I was younger."

He adds: "I will remember that for the rest of my life. I was being invested in, and that makes you completely loyal."

Olympic training

The cyclist dubbed the Manx Missile admits he will never be a winner of the Tour de France yellow jersey, awarded to the racer who completes the Tour in the shortest overall finishing time.

That is because his speciality is sprinting to the finish line, with flat race stages of the type he favours making up just less than half of the race.

Image caption Cavendish is hoping to please his British fans at the Olympics

He compares his speedy speciality finish, usually in competition with dozens of other sprinters, as being akin to having all 20 Premier League football teams on the same pitch at the same time, "all trying to score in the same goal in the last minute of the game".

However, he expects to be less dominant in the sprints in this year's Tour than in previous years, after making some changes to his training methods and losing weight as part of his preparations for the Olympic race.

That is because he does not believe the London 2012 road race will end with a massive bunch-type sprint to which he is used.

As part of his detailed training for the Olympic race, he has been increasing his endurance training, and at his home base in Italy thinks nothing of taking part in five consecutive 11km climbs in quick succession.

'Honour'

In mid-June, Cavendish achieved another career milestone when he won the Ster ZLM Toer in Holland.

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It was the first general classification win of his career, that is in a race where the winner is the rider who has the fastest time when all the stage results are added together.

"It is a benchmark in my career," says the 2011 Road Race World Champion, who is now one of British cycling' s most recognised names alongside the likes of Bradley Wiggins or Chris Hoy.

"When I started in cycling it was not such a big sport. Cycling is now being recognised as a big sport, it is massive, and it is an honour to be a part of it."