Marathon Swimmer Martin Strel is Nuts

'He swam the English Channel and became the first man to swim across the Mediterranean. Seven men had already died in the attempt, either drowned or eaten by sharks. He then took on the Danube, before swimming the Mississippi, the Argentine Parana and the Yangtze in China, an experience which left his liver black. He also swam London's River Thames last year, although its risks were somewhat less than the Yangtze. Lastly he swam the legendary Amazon. That's 3,274 miles, swimming 10 hours a day for 66 days.. on two bottles of wine a day *or 196,440 lengths of your average pool.'

He's middle-aged, his ample belly bulges over his Speedos... and he thinks drinking two bottles of wine a day keeps him in shape. Swimmer Martin Strel would be the first to admit he makes the unlikeliest of athletes. But the 55-year-old harddrinking Slovenian just happens to be the greatest endurance swimmer in the world... ever.

He claimed the title by conquering the world's most dangerous river - the Amazon - swimming 3,274 miles in 66 days, non-stop. "It helps to be a little crazy, to do what I do," Martin admits. "I told myself that I would swim the Amazon or I would die trying. "I'm a big man, sure, but the Amazon is so much bigger." The astonishing story of courage and determination is the subject of a new movie, Big River Man, which opens across the UK next month. The enthralling film sees Martin brave the constant threat of piranhas, crocodiles and the horrifying candiru fish. He also had to battle through tropical storms and blistering heat, as well as facing murderous bandits and machetewielding native tribes. Add unrelenting diarhea to that catalogue of horrors and you get an idea of the type of man Martin is, tackling each obstacle with sheer bloody-mindedness... and a healthy dose of alcohol.

But even as he tells how his doctor warned him to give up drinking to lessen the risk of heart attack, Martin simply cracks open another bottle of red, washing it down with a whisky and some beer. "I told the doctor I have to drink, I have to swim - I am Martin!" says the part-time guitar teacher.

As a child, he used to leap into the icy river near his home to escape beatings by his father, but he didn't begin serious endurance swimming until 1992. His first challenge saw him conquer the 65-mile Krka river in his homeland in 28 hours. He then swam the English Channel and became the first man to swim across the Mediterranean. Seven men had already died in the attempt, either drowned or eaten by sharks. He then took on the Danube, before swimming the Mississippi, the Argentine Parana and the Yangtze in China, an experience which left his liver black. He also swam London's River Thames last year, although its risks were somewhat less than the Yangtze. Martin says: "The Thames was a little easier to swim than other rivers. I thought it was a very nice, clean river. But it was very cold."

After such previous conquests, the Amazon must have seemed like a natural progression. Martin trained more than five hours a day in his local swimming pool and finally began history's longest swim in April 2007. His daily target was to swim for 10 hours every day, covering around 90km. But the adventure soon became a struggle for survival. As well as dehydration and exhaustion, water-borne parasites left his body racked with infection and disease, including dengue fever, which triggers painful cramps.

Tarantulas, giant millipedes and scorpions would drop off the trees into the river, often getting entangled in his hair. Birds would fly down and attempt to peck at his face. Larvae burrowed into his skin and his face was stung by wasps. Some days he even had to wear a pillowcase over his head, with slits for the eyes and mouth to protect his face from the heat. However the hazards above the water were nothing compared to the horrors below.

The biggest danger was the bull shark, responsible for the deaths of more humans than any other type of shark in the area. Then there are stingrays and anacondas lurking in the shallows, crocodiles and alligators that can seize human-size prey and gobble it whole. Long, poisonous snakes slither out of nowhere and giant catfish up to 15ft long, known to swallow dogs and children, hide in the mud. Once he had to be hauled from the water screaming in pain, as shoals of piranha fish gnawed at his leg. He swam in the faster-flowing middle of the channel, in places 100ft deep, in the worst Amazon floods for a century, but sometime he couldn't avoid the stiller water. In an attempt to stop the razorjawed piranha fish from smelling him, Martin would lather his body with gasoline and cream and buckets of pigs' blood would be thrown into the water to divert their attention. But of all the dangers, the one Martin feared most was the tiny candiru, otherwise known as the vampire fish, a parasite with a vicious tactic. It is attracted by the scent of urine and enters the body by swimming up the penis. Once inside it locks itself on with a series of spikes and feeds off blood and tissue. Surgery is the only way to remove it. And if Martin was attacked the nearest emergency ward was hundreds of miles away. To reduce the risk, Martin never exposed himself to urinate and always did it inside his wetsuit. "I never looked down," he said.

The only friendly creatures he met were the porpoises and dolphins who often kept him company, swimming alongside. His escort boat, skippered by his son and manager Borut, 28, had a team of armed guards to protect him from river pirates and carried his stockpile of medicine and food...and alcohol. "Drinking wine is part of my life," Martin says. "It's my special blend, that I make myself, so it's very healthy and it gives me energy, without making me drunk. I would drink whisky as well, to wash my mouth out before I eat food. "But sometimes I drank a little just to lift the day, because to swim a river like the Amazon is very hard. You never know what is below the water - and a drink helped me relax. You need a little Dutch courage!" The toll on his body was immense - he weighed 114kg (250lb) when he started and lost nearly 20kg (44lb) during the swim, despite being on an 11,000 calories a-day diet to keep up his strength. Towards the end, he admitted that it felt like "a bomb was about to explode" in his head. He took months to recover. Since his swim, which he undertook to highlight increasing levels of pollution in the world and the threat to the rainforests, Martin has become a huge star back home in Slovenia. Nowadays, women flock around him, calling him a hero and begging to be his wife. "Yes, I get hit on a lot and sure, I do like pretty ladies," Martin says. "But I'm already married. I have to keep my head clear - just as I did when I took on that river. "I am just a regular man who just has higher goals than usual, not a superman." So what's next for the incredible human fish? "Who knows?" shrugs Martin. "Maybe I'll swim right around the world!" Big River Man is in cinemas from September 4.

Some of the horrors under the water...

BULL SHARK Needs no introduction, this is more of a maneater than even the legendary Great White

ANACONDA Less of a snake, more of a scaly submarine, this beast is best avoided at all costs

PIRANHA Shoals are famed for being able to strip a cow to the bone in under a minute

CANDIRU Known as the vampire fish, its methods are enough to make men scream like little girls

Amazon facts The river is 3274 miles long. Only the River Nile in Egypt, at 4,132 miles, is longer. It pumps 300,000 cubic metres of water a second into the Atlantic. It accounts for a fifth of the world's fresh water. It is home to a third of all the species of animals in the world. There is no bridge across it. At its mouth in Brazil, it is 210 miles wide, which is wider than the length of the Thames. The source of the Amazon is a stream in the Peruvian Andes.