One kick in the head, and your Olympic Games can be over. But there's no punching to the face. That's taekwondo, in the Games for the third time, with Britain still seeking a first medal.

Team leader Gary Hall believes it could come this time, even though two of his three players aren't out of their teens. With a Cuban coach, who swears he is not teaching revolutionary habits to his proteges, Hall could be right.

Sarah Stevenson was just 17 when she went to Sydney in 2000, and missed bronze by a point. She did it with no support, but that has all changed. Now 25 and a former world champion, she's the "granny" of the squad. It also comprises two baby-faced assassins, 17-year-old Aaron Cook and 18-year-old Michael Harvey.

Cook's calm confidence is remarkable. He seems not at all intimidated by double Olympic champion Steven Lopez. Would he like to face his idol in the first round?

"Why not?" he says. "Lopez is a hero of mine because he's No.1. I've always wanted to beat him, and now he's coming towards the end of his career, I'm not going to get many chances to fight him. I've dreamt about an Olympic final with him, and I'm going to do my best to try and get there. If he's in the final with me, God help him.In the dream, I knock him out . . . I've knocked a lot of people out.

"How does that feel? Well it feels pretty good, but it feels pretty bad for them."

With three two-minute rounds, he says, it's a lot better than going the distance. "I've never been knocked out."

Stevenson supports Cook's style: "You could make a mistake, or your opponent could do something outstanding," she said.

"Steven Lopez might have won everything there is to win, but Aaron could kick him in the head and knock him out. It could happen to anybody."

The six-foot welterweight became the first British male to win a world junior title this year. He has also been European cadet and junior champion, and won gold at last year's Youth Olympics.

His success has prompted his family to up sticks from Dorchester (where he started in the sport aged five) to train full-time at the sport's academy in Manchester. "They do my washing and ironing, and cooking," he says. "It's nice of them."

He's certainly had it easier than Stevenson. "I'd no support at all," she says, without a hint of jealousy at the boys' lottery support: "I think it's great. I don't want anyone in the situation that I was in when I was 17."

She proved the catalyst for change. In 2001, on the Korean island of Jeju, she was crowned world champion. She has a commemorative tattoo on her left ankle: Jeju, the Olympic rings, and "taekwondo" in Hangul script.

She beat the Chinese Olympic champion, Chen Zhong, in the final. "I didn't even know who she was when I fought her," she said, "not till after I'd finished. She had been in a different weight group in 2000.

"Support kicked in after that. Before, I'd worked as a secretary, but I don't think I will ever go back to that."

She is clearly impressed by Cook. "Help him? I don't think he needs my help, and I'm not sure he'd take it if I offered," she says.

The squad has footage of every fighter in Beijing, and a private room near the venue to study the data and plan in the three hours between matches. "We know their trends, their strong points," says Hall. "Our analyst will be joining us in Beijing, setting us for every match, so it will be fresh."

Their attention to detail is meticulous. Mike Hay, the deputy director of the Macau camp, said: "They asked me to simulate the Beijing arena here in Macau. There's a raised platform, with sloping sides, so we got a squad of Chinese joiners, and built it as an exact match here. We have put in the same colour of mats, even the same decoration and posters: Beijing 2008."

Their Cuban coach, Nelson Miller, won world bronze in 1997. His nation has a production line of champions despite dreadful deprivation and minimal support.

British resources stunned him. "When I saw the accommodation, and all the advantages, compared with my country, it is huge. Sometimes I ask myself what would happen if Cuba had the same money you have.

"It's very impressive to see how some countries do it for love, some because they have a lot of things to lose, or because it's a way of life. But sometimes, when you see some players play only for money, and see that some of them have no love for the country - it's a huge difference.

"The difference now, we have in the British academy a combination between young and old players. We have a generation which is very good.

"Some of them learn with the passion of a lover, and passion for the sport, and some of them learn how they can make a life."

Has he tried to impose some of his Cuban culture?

"It's different, the culture. I learned in a Communist state. I was a revolutionary . . . I try to change nothing, just the performance. I try to put more fighting spirit in the players, not change the culture."

The man to beat

Steven Lopez has won four world titles and is bidding for his third successive Olympic gold. He is one of three siblings in the US team, first time this has happened since the 1904 Olympics. His younger brother, Mark, and sister Diana are also in the team which is coached by their elder brother, Jean. He taught them the sport along with their father in the family garage. The trio made history in 2005 when they all won titles at the world championships. In 2006 Steven Lopez tested positive for an L-methamphetamine, which he said had come from an over-the-counter inhaler. This was what cost Alain Baxter Olympic bronze, and like the Scottish skier he received a three-month suspension.