It is a brilliant late autumn day, and the surrounding hills blaze with reds and gold, but the 3,000 people packed into an open-sided pavilion in downtown Chattanooga have other things on their mind. They are awaiting the biggest sporting event in the history of this Tennessee city: no, not the national tae kwon do competition taking place just down the road, but the Hamburger Eating Championship of the World.

It is all razzmatazz — balloons, a rock band, free T-shirts galore. The MC, a dapper fellow decked out in boater and blazer, whips up the crowd. “We’re here to see history made,” he declares. “We are here for one of the biggest tests of the human will,” he proclaims. “This is not just a sport. It’s a lens on to the human spirit.” A boys’ choir sings The Star-Spangled Banner. A marching band oompahs in — all swinging arms, bare legs and gleaming brass. Then a motorcade of open-topped Corvette sports cars starts delivering the contestants themselves into the heart of the whooping melée.

The lesser ones come first. There’s Justin Mih, a 29-year-old molecular biology student from Harvard. “From his earliest days he had one big dream,” the MC announces. “He always wanted to be on stage alongside the greatest eaters of his age.”

There’s Seaver “The Achiever” Miller, a 28-year-old fireman from Virginia — “he comes here today after saving women, children and kittens from burning homes”. There is Rich “The Locust” Le Fevre, at 62 the grandfather of the competitive eating circuit but still the world Spam-eating champion, having once consumed 6lb of the stuff in 12 minutes flat. He recently set another record by swallowing 247 pickled jalapeno peppers in just eight minutes.

And here come the bigger guns — “Crazy Legs” Conti, a dreadlocked New York window cleaner whom the MC dubs the “Evil Knievel of the alimentary canal”; Pat “Deep Dish” Bertoletti, 21 and mohawked, who ranks fourth in the world at competitive eating; and Sonya Thomas — 39 and thin as a toothpick — who ranks third. She is a South Korean immigrant called “ The Black Widow” after the spider that eliminates males. She has downed 65 hard-boiled eggs in six minutes, 11lb of cheesecake in nine minutes and 46 dozen oysters in ten minutes.

But there are two out-and-out front-runners this afternoon. One is Joey Chestnut, a 22-year-old engineering student from California and the great American hope. The other is Takeru Kobayashi, a baby-faced wisp from Japan who, at 27, has already established himself as the Tiger Woods or Michael Jordan of competitive eating. The “Human Tsunami” has won the July 4 Nathan’s hot dog eating championship in Coney Island, New York — the sport’s equivalent of Wimbledon or the World Cup final — six years running, and once devoured 57 cow brains in 15 minutes.

“Is he a man, or is he a demigod?”, the MC asks in awed tones. “He’s a warrior born to battle. He’s a boy king. He is the greatest athlete of all time . . .” The 13 finalists, winnowed down from the thousands who entered qualifying contests in eight cities, make their way to the stage where the MC explains the rules: the contestants have eight minutes to eat as many burgers — replete with buns, onions and mustard — as they can. The burgers may be dunked in liquid to make them slip down more easily, but for no more than five seconds. Vomiting means automatic disqualification.

This is the rematch that the world of competitive eating has long been awaiting. Last year Chestnut led until Kobayashi swept past him in the final minute to set a new world record of 69 burgers. It is, as the MC tells us, “the clash of the Titans” with a $30,000 purse.

The contestants or “gurgitators” line up behind a long table, each with a row of outsized plastic cups. Employees of Krystal, a southern fast-food chain sponsoring the event, bring on trays of hamburgers, each in a small box. Beauties with score cards take their places behind the contestants, judges in front. The MC starts the countdown — “Ten, nine, eight . . .” Suddenly they are off, a frenzied blur of flying hands and gaping mouths and bobbing heads. It’s best not to be within the spray zone . . .

On the face of it, competitive eating is America at its most decadent. It glorifies gluttony in a land where two thirds of adults are already obese or overweight. It carries the country’s culture of excess, commercialism and empty celebrity to absurd lengths. It is grist to the mill of those who dismiss Americans as fat, crass and puerile, and — surely — the antithesis of true sport.

Competitive eating certainly does not promote good health. It demands no athletic prowess. It turns ordinary folk into the human equivalents of foie gras geese in return for brief moments in the limelight.

And now it is coming to Britain. The first official contest will take place at Wookey Hole Caverns in Somerset tomorrow, with Sonya Thomas taking on 11 other contestants in a mince pie eating contest sponsored, appropriately, by the former circus owner Gerry Cottle. The winner will take home £1,000.

But there is another way of viewing competititive eating, which is as a bit of self-mockery, a joke at America’s own expense, almost a parody of that country’s mainstream sports with all their pomposity, self-importance and overpaid superstars. That is more or less how it began. It is a “sport” invented not by its participants, but by a couple of public relations men with a keen sense of humour and an eye for the main chance.