Boiled cabbage and rice for breakfast may have been stretching the point, but at boot camp for wannabe Olympians and Paralympians, nothing is sugar-coated. Presumably, once you have won three Olympic gold medals like Chris Hoy, you are allowed to start your day with a bowl of Bran Flakes.

For the 80 British teenagers handpicked from six sports — canoeing, cycling, hockey, rowing, sailing and wheelchair basketball — the meagre rations are part of a process to discover whether they have what it takes to become the best in the world. After four days at the annual National Talent Orientation Camp at Loughborough University, organised by the Youth Sport Trust, many will arrive at an unpalatable truth: despite talent, they just don’t want that medal badly enough if it means years of pain, disappointment and sacrifice.

“The greatest athletes are not necessarily the ones with the greatest innate talent, but the ones with the greatest desire,” said Sue Campbell, who chairs the trust and UK Sport, the Government’s funding agency for Olympic athletes. “The sexy bit is standing on the podium, waving from the top of a bus and winning BBC Sports Personality of the Year. The unsexy bit is the blood, sweat and tears.”

The camp, funded by the Department for Children, Schools and Families, poses the difficult questions that young athletes may not have asked: what is my dream? What will I give up to achieve it? Can I perform when it counts? What if I fail?

As most of the participants have finished or are approaching their GCSEs, it is not unreasonable to think that they have not mapped out their careers. “I don’t think many people know what they want to be doing in ten years,” Patrick Galbraith, 15, an endurance cyclist from Edinburgh, said. “I prefer thinking season to season. After that, it’s a blank patch.”

However, he insists that he does know he wants to be an Olympian. By virtue of being at the camp at all, British Cycling officials think that he has the talent. The rest is up to him.

Jason Gardener, part of the men’s 4 x 100 metres relay team that won gold in the Athens Olympics in 2004, is one of seven athlete tutors sharing their highs and lows. “I wish I had something like this when I was young,” he said. “I was just stumbling in the dark. These kids stand ahead of the rest but they need to know what the Hoys have gone through. If you turn on the TV and see people winning all the time, you think it’s easy. Nothing is easy in this world and this kind of life is not for everyone. Better to recognise that now than on the start line, realising you are not as good as you thought you were.”

All sports are packed with cautionary tales of the most talented individuals falling by the wayside because they did not want to do the hard yards. This would not be a boot camp without the 6am wake-up call for circuit training and night-time army command tasks but the most important aspects relate to mental attitude.

There is the “reaching the summit” analogy from Jake Meyer, who, at 21, became the youngest Briton to climb Everest, and tips on how to “train your chimp” by Steve Peters, British Cycling’s elite team psychiatrist who helped Victoria Pendleton.

Their determination is measured by how long they can hold a litre bottle of water with straight arms at 90 degrees — a canoeist proved the most dogged, ignoring the pain for more than 12 minutes to break the camp record and impressing Ian Wynne, who won a bronze medal in the 1,500 metres flatwater canoe in Athens.

The camp organisers hope to prepare potential Olympians for the slog ahead while helping them to keep other education and career options open. “These are the ones with the extra spark pushing for the Olympic development squad but do they really understand what it takes?” Simon Wergan, the youth racing manager for British Sailing, asked. “They have to make that choice. The last thing we want is an athlete investing the years between 16 and 25 and then finding out they wished they had done something else.”

They probably do not yet know whether they have the stomach for it. An easier life beckons for some but the hungry ones would eat gruel every day for an Olympic medal. Pain? Please, sir, can I have some more?

Generation building

- Fourteen to 18-year-olds are selected from six sports not part of the UK School Games

- There are seven athletes’ tutors: Jason Gardener (athletics), Miriam Batten (rowing), James McCallum (cycling), Clare Strange (wheelchair basketball), John Bleby (hockey), Ian Wynne (canoeing), Joe Glanfield (sailing)

- There are four themes: talent and ability; attitude and ambition; knowledge and understanding; education and lifestyle support

- Nine out of ten participants are more positive in training after the camp and 94 per cent are hungrier for success