Usain Bolt has been backed by British athletes past and present to continue his phenomenal rise and eventually clock 9.4 seconds for the 100 metres.

Bolt stunned the World Championships in Berlin on Sunday night when he won gold in a time of 9.58, shaving a jaw-dropping 0.11 off the record he set in Beijing last year.

The question now facing Bolt and athletics is just how fast the 22-year-old Jamaican - and the human body in general - is capable of running.

Bolt claims 9.4 is possible and former junior world champion Mark Lewis-Francis, who anchored Britain to gold in the 4x100 metres relay at the 2004 Athens Olympics, agrees.

"Berlin's not known to be a fast track so I reckon Bolt could go sub-9.5 and run 9.4," Lewis-Francis told BBC Radio 5Live.

"But once he retires I don't think his will be the record that stands. Technology is changing.

"By 2012 I think he will have done something crazy because the technology of track and field is changing.

"I think he can run even faster. And if he's done that in the 100m, what can he do in the 200m?"

A biomechanical analysis of Sunday night's final reveals that Bolt was in front from start to finish and established a significant lead of 0.06 seconds after just 40m.

The triple Olympic gold medalist is considered to be at his weakest at the start but he was the fastest after 20m by 0.01.

Former European 400 metres champion Iwan Thomas believes Bolt's unique blend of ability and physique will enable him to run faster still.

"Bolt is a one-off. I remember racing Michael Johnson and thinking 'this guy's a freak, who's ever going to run faster than 19.32 for the 200m?'. But look at Bolt," he said.

"Obviously the human body can only run so fast - I don't know what that point is but something would go wrong.

"But if the rumours are true and he's run 9.5 in training, without a crowd or adrenaline, then maybe he can run 9.4.

"I wouldn't bet against anything he says. With a big tail wind, just how fast can he run? It looked easy for him last night.

"The guy is a machine, he's amazing. Six foot is regarded as quite a tall sprinter but Bolt is tall and has such a long stride length, with the leg speed to match.

"There has to be a limit somewhere, but Bolt is so relaxed and never looks under pressure."

Ron Maughan, a professor of sport and exercise nutrition at Loughborough University, denies statistical evidence that claims the fastest the human can run 100 metres is 9.51secs.

"It's right to say the records have been decreasing in time in a straight line for some time so why shouldn't they continue to decrease?" he said.

"But there is a limit somewhere, where that is we don't known.

"The problem with the statistical analysis is that it looks only at past history.

"It doesn't look at things like better training, shoes and tracks. I think we'll continue to see improvements."