Oscar Pistorius calls himself the world's fastest man on no legs.
The runner was born with bones missing in his legs, which required amputation below the knee shortly after his birth. But don't call Pistorius disabled — he could very well be the fastest man on any legs if he only gets the chance.
The South African has lived most of his life as a double amputee, but he never let his disability keep him from achieving any of his hopes and dreams.
"I never encountered anything that I couldn't do, due to the fact that I had prosthetic legs," Pistorius told ABC News' John Berman.
"Obviously, if I had wanted to do something like ballet, I might have struggled," he said with a slight chuckle and grin.
One of those dreams was to become a competitive runner, and thanks to high-tech prosthetics called Cheetah Flex Feet made by Ossur, Pistorius took off running and hasn't stopped.
The Blurring Line Between Disabled and Able
At just 20 years old, Pistorius is already shattering records for Paralympics athletes. He set a world record at his first major competition, the 2004 Summer Paralympics in Athens. He earned a gold medal with a time of 21.97 in the 200-meter race.
A year later, he topped his previous record at the 2005 Paralympics World Cup, winning gold in both the 100 meter and 200 meter. And in 2006, Pistorius again shattered the 200-meter record as he took home first place in the 100-meter, 200-meter and 400-meter events.
Now, he has his sights set on an even bigger competition: the 2008 Olympic Games.
"My dream is to compete in at least two Olympic Games," Pistorius said.
It is a dream within reach. Pistorius has been beating able-bodied athletes, finishing second in the 400-meter race at the South African nationals early this year. But his biggest obstacle to his Olympic goal isn't other runners.
From Disability to Unfair Advantage?
The International Association of Athletics Federations, the governing body of track and field events, said Pistorius' prosthetic limbs might not be a disability at all. Spokesman Robert Hersh said they may give him an edge over runners with legs.
"They could be making him taller, giving him a bounce, a spring," said Hersh. "What we need to make sure of is that he's not using something which could give him an unfair advantage."
The Cheetahs are J-shaped carbon-fiber prosthetics that might be built stronger than the legs most humans are born with. But the Cheetahs give back only about 30 percent of the energy that a human leg would. Pistorius said the accusations that he's benefited from his fake limbs were ridiculous.
"I can't see that a prosthetic can be seen as an advantage," said Pistorius. "It is such a weird concept to think about."
The IAAF is still studying Pistorius' case but has proposed a rule that could prohibit him from partaking in Olympic competition. The most recent roadblock frustrates Pistorius, providing him with a challenge that will take more than sweat and sheer determination to overcome.
"That is like pure discrimination against disabled people and the fairness of sport," said Pistorius of the IAAF's proposal.
Pistorius said he just wanted the chance to run a fair race on the legs he was given.
The athlete told "GMA's" Robin Roberts that his competitors and coaches had been supportive.
"The guys that I ran against are very supportive and that's been great," he said. "They're pretty happy I'm training and bridging that gap between Paralympics and Olympic sports."