The five-mile high octogenarian contest: 80-year-old man begins quest to become oldest man to climb Mount Everest... but 81-year-old rival also seeks title

Yuichiro Miura, 80, who has had heart surgery four times is already in the oxygen-deficient 'death zone'

Call it the five-mile high octogenarian contest the likes of which have never been seen before.

Or at least not since five years ago, when two rival mountaineers, now aged in the 80s, previously did battle on the slopes of Mount Everest when they were both in their relatively youthful 70s.

On Wednesday it was revealed that Japanese climber and extreme skier, Yuichiro Miura, aged 80, was already in Everest’s “death zone” above 8,000 metres, where oxygen thins and the smallest mistake or flux in the weather can turn fatal.

Yet if he did not have enough to worry about, it emerged that close on his heels is the 81-year-old Nepalese man, Min Bahadur Sherchan, who snuck in before him back in 2008 to claim the record for the oldest climber.

On his website, the Japanese climber has explained that he is trying to push himself to the very limits of what is possible, both for himself and people of his age. He said his climb is partly a pilgrimage. He also claims that at 8,000m, the body automatically acts as if it is 70 years older – meaning that his physical capability is that of someone aged 150.

“It is to challenge my own ultimate limit. It is to honour the great Mother Nature,” said Mr Miura, who has apparently reached the South Col, the point from where most climbers launch their bids for the summit. “And if the limit of age 80 is at the summit of Mt Everest, the highest place on earth, one can never be happier.”

Even to be where he is, is a remarkable achievement for the Japanese adventurer. In 2009, he fractured his pelvis and left thigh bone in a skiing accident and in January he underwent an operation to correct an irregular heartbeat. It was his fourth such surgery.

“If he was in his 60s, he probably would have waited for another year or two, but at the age of 80 he's not getting any younger. He has a strong determination that now is the time,” his daughter, Emili Miura, told the Associated Press.

If Mr Miura makes it to the top, he would capture the record. But it would only last a few days if Mr Sherchan is able to follow his him.

The situation is little different to how things played out in 2008 when, at the age of 75, Mr Miura sought to recapture the title of oldest man to summit the mountain. He had set the record in 2003 at the age of 70 but it was later broken twice by slightly older Japanese climbers.

He reached the summit on May 26, 2008, at the age of 75 years and 227 days. But the record cruelly eluded him because Mr Sherchan had scaled the summit the previous day at the age of 76 years and 340 days.

Mr Sherchan, a former Gurkha soldier in the British army who began mountaineering in 1960, walked the length of Nepal in 2003. He and his team said they will make their attempt next week, just as Nepalese officials are celebrating the 60 anniversary of the first successful attempt on Everest by Edmund Hillary and Tenzing Norgay in 1953.

“Our team leader has just arrived back at base camp and we are holding a team meeting on when exactly I will head up to the summit,” Mr Sherchan told the AP, speaking from base camp. “I am fine and in good health. I am ready to take up the challenge. Our plan is to reach the summit within one week.”

His rival, the Japanese climber, Miura was well-known long before his late-in-life mountaineering pursuits. A celebrated speed skier who described the South Col in 1970, using a parachute to slow his ride, he was featured in a subsequent Oscar-winning documentary The Man Who Skied Down Everest.