The man who is going to run 52 marathons around the world in 52 weeks

Meet Australia's very own marathon man. Tristan Miller aims to become the first person to run 52 marathons around the world in 52 weeks.

The 32-year-old will visit at least 42 countries, clocking up more than 260,000 kilometres in the air.

He will undertake the first 42-kilometre foot slog of his epic journey in Zurich, Switzerland, on January 1.

Mr Miller's travels will also take him to the Running of the Bulls in Pamplona, Spain, as well as races in such diverse countries, cultures and climates as Siberia, Dubai, South Africa, Slovakia, Northern Ireland, Cuba and the Cayman Islands.

He plans to finish his journey in his home city of Melbourne with a marathon he plans to stage himself, hoping to have at least 100 fellow runners join him.

The $150,000 trip will cost him his life savings – including the sale of his St Kilda apartment, his car and most of his possessions but he is hoping to attract sponsors and is determined to raise $100,000 for UNICEF through donations.

Mr Miller, in Sydney to say goodbye to his father, brother and other family and friends, said people he had spoken to about the journey had the same reaction.

"Everyone is like, 'You're just nuts. Why would you bother?' " he said. "I just want to do something different. I'll start over again when I get back."

The IT specialist only began running five years ago, as a way of dealing with the breakdown of his marriage.

He soon found that running long distances gave him a sense of achievement and the courage to try other things he never dreamed he could do, such as taking off on a whim to explore exotic locations.

When he was made redundant from his job at Google in April, Mr Miller decided to combine his new pastimes and put his body to the ultimate challenge.

He has only done five registered marathons, including the Canberra and Melbourne events twice each, and the 87-kilometre ultra marathon Comrades in Durban, South Africa.

He will prepare all his own meals, with food poisoning not an option despite the temptation of exotic cuisines.

He knows that injuries are a distinct possibility, with "runner's knee" already proving to be a problem.

"The patella is not tracking right," he said. "It is quite curable, I have just got to do strengthening. It does not help me that I am running and grinding away on my kneecap."

Lisa Holmes, the editor of Runners World Australia and New Zealand magazine said that Mr Miller's attempt was the first that she was aware of and certainly the first time an Australian had undertaken such a feat.

"Hopefully he can do it – it will be a great achievement," Ms Holmes said.

"He has got different climates [to deal with].

"That will be his challenge and I am sure he will be wearing lots of compression wear on flights."