As sporting records go, it will be one of the toughest to crack. If Andy Ripley succeeds in his ambition to row for Cambridge next March, he will be the oldest ever blue in any major sport.
Mr Ripley, who has already made the 28-man training squad from which the Cambridge crew will be selected, will have to overcome declining lung and muscle function which are the inevitable legacy of age. But his fanatical fitness regime over the years since he was an England rugby international have given him an edge over younger rivals.
If selected, Mr Ripley's achievement would put other ageing sports stars in the shade. Stanley Matthews played his last game for Stoke City in 1965 at the age of 50, having spent 33 years in the football league, Peter Shilton retired as goalkeeper for Leyton Orient last season aged 47, and George Forman is still boxing more than two decades after his famous defeat by Muhammed Ali in the "rumble in the jungle" clash in Zaire in the 1970s. But none of these compares in terms of the physical demands that will be made on Mr Ripley.
At 6ft 5ins and weighing 17 stone the accountancy postgraduate is a huge man with extraordinary aerobic fitness. He could run the 400m hurdles in under 53 seconds and took up triathlons in his forties. He ranked second last weekend in tests of strength output over six minutes, beating men half his age.
Robin Williams, the Cambridge coach said: "He is a big strong fit guy who despite the fact that he is twice the age of the people trialling with him is performing very well. By rights no one his age should be in with a shout, but he clearly is."
Mr Williams said that in addition to strength and fitness, rowing technique was "massively important" as was the compatibility of the final crew. "How the eight fit together matters. Last year, Oxford had greater pulling power but we won."
The boat race lasts 15 to 20 minutes, depending on wind and tide, and is one of the toughest of all endurance races. It is quite different from rugby, with its stops and starts, and success depends on strength and the body's capacity to use oxygen efficiently.
Although Mr Ripley has been a champion indoor rower in his age group for many years and a winner of the BBC Superstars series, he will have to prove himself against younger men.
Dr Stephen Boutcher, an exercise physiologist at the University of Exeter, said there was a decline in people's aerobic power after the third decade. Although training could postpone the decline, it could not stop it.
"I would expect even a highly trained athlete in their fifties to have an aerobic capacity below that of an athlete in their twenties. Even if you train tremendously hard you will not achieve the level of fitness you had then. The older you get the harder it is."