Weyand, the scientist with the treadmills, believes that Pistorius's prosthetics allow him to move in a way that no non-prosthetics wearer could, giving him an advantage.
Kram, the biomechanics expert, believes that the Blade Runner's blades hinder him just as much as they help. One of the biggest points of contention is limb-repositioning time. The average elite male sprinter moves his leg from back to front in 0. The five most recent world record holders in the meter dash averaged 0. Pistorius swings his leg in 0. Pistorius's rivals are swinging a lower leg that weighs about 5. Kram and his researchers countered with a paper claiming to have measured Walter Dix, a meter sprinter, swinging his leg faster than Pistorius.
But they used television footage of Dix rather than the standard, high-speed research video generally used to make such measurements. High-speed footage for Dix from that same season does exist, Weyand says, and it shows the runner clearly repositioning his limbs at around the same rate as the average Olympic sprinter.
Swing time is important because it affects some central factors that determine how fast a person can run. Repositioning his legs faster means Pistorius can keep his foot on the ground longer than everyone else. It's a bit counterintuitive, but Weyand argues that a runner's speed is largely determined by how long he can keep his feet on the ground, rather than in the air.
The longer a foot remains on the ground, the more time the person has to generate force that will propel him forward. More force generally means more speed. Kram argues, however, that because the Cheetahs are made of carbon fiber, and are lighter, they can't transmit nearly as much force to the ground as a human leg can, creating less forward propulsion.
So Pistorius has to push down harder than most people to get the same amount of force against the ground. Weyand counters that Pistorius simply doesn't need to push as hard to run just as fast.
A runner using biological limbs can also adjust the stiffness of leg muscles and the angle at which a foot strikes the ground on the fly to accommodate any changes in a running surface. But the stiffness and shape of a blade cannot be changed once it has been fitted to the runner, as it is custom-optimized for a particular athlete to run under very specific conditions. The blades do have competitive benefits, however.
Researchers who have studied blade prostheses disagree fiercely over the net impact of these pros and cons on overall performance. The researchers concluded that Pistorius used 17 percent less energy than that of elite sprinters on intact limbs. The tests also revealed that it took the South African 21 percent less time to reposition, or swing, his legs between strides. Big disagreements arose over how to interpret the research. The sprinter would go on to compete in the meter and meter relay races at the Summer Olympics in London.
Rehm, whose lower right leg was severely damaged by a boat propeller when he was a teenager, won the German national long jump title in In , as Rehm sought a way to continue competing in mainstream events, the IAAF changed its rules , requiring amputee athletes prove a prosthesis does not give them an edge.
In September, the IPC had said that it would not block Pistorius, who has won six gold medals at three Paralympic Games, if he had served his sentence and wanted to compete at Rio. What we've said throughout this is that we would respect whatever decision is made by the South African court," said Craig Spence, director of communications for the IPC. Spence added: "Regardless of whether Oscar comes back or not, the Paralympic movement goes from strength to strength.
Asked what he would say to Pistorius about a potential return after his ban has been served, Spence said: "I would say it is purely his decision. Pistorius, nicknamed Blade Runner after the prosthetic limbs that replace the lower part of his legs, made history by becoming the first amputee sprinter to compete at the Olympics during London He also became the first Paralympian to win an able-bodied world championship medal when South Africa finished second in the 4xm relay in Pistorius did not run in the final but was eligible for a silver medal as he ran in the heats.
The International Olympic Committee has yet to reveal its stance on whether it will allow him to compete at its events again. But, in a statement, the IOC said: "We take note of the court's decision.
I contend that the best method for deciding whether or not Pistorius is competing in the same sport as able-bodied athletes is to adopt a balance of excellences view of sport Devine, I use this model to show that the excellence of exploiting technical aids is far more important for Pistorius than it is for his able-bodied counterparts.
From this I conclude that what Pistorius does when he runs is not comparable to able-bodied runners. Thus he should not be allowed to compete against able-bodied athletes at the Olympic Games.
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