There’s no doubt. Watching Oscar Pistorius run is awe-inspiring. Here’s a guy, who was born without shin bones, who kicks dust in the eyes of some of the world’s top athletes.
But Pistorius’s participation in international athletics has been shrouded in controversy. The latest public spat revolves around whether Pistorius should be allowed to run against able-bodied athletes in the 2008 Beijing Olympics.
Thanks to advanced biomechanical tests that will be conducted in Germany during the next six months, the International Association of Athletics Federation (IAAF) should soon have a more conclusive answer.
In the meantime, however, Health24 caught up with the local experts.
Pistorius might have an advantage
In 2005, Health24 ran an article on Pistorius which investigated the pros and cons of running with prostheses. At the time, sports scientist Dr Ross Tucker from the Sports Science Institute of South Africa (SSISA) predicted that Pistorius would fare better in the 400m event than in the 100m and 200m events, in which he initially participated.
We now know that this is true.
Tucker explained that Pistorius’s artificial limbs made balancing at the starting blocks difficult and that he lost a lot of time here. Furthermore, it was clear that Pistorius’s overall balance during a race couldn’t be compared to that of an able-bodied athlete and that he had nothing like the fine motor control that is added by having a calves, ankles and feet.
Two years later, a lot has been said and written about Pistorius’s remarkable ability to run. But Tucker’s opinion has changed. “The evidence is strongly suggestive of an advantage,” he says.
From test results, it’s clear that Pistorius makes up for lost time towards the end of a race. While other athletes usually get slower as the race progresses, Pistorius gets faster.
According to the experts, three factors could be contributing – though no definite conclusions can be made as yet:
1. the carbon-fibre blades provide less air resistance than normal legs;
2. the spring action of the blades could be propelling him forward; and
3. the blades never fatigue.
Cheetah blades vs. human legs
On 13 July 2007, Pistorius was filmed by two high-definition cameras at the Rome Golden Gala in Italy.
According to the Associated Press, the IAAF analysed the footage and found that Pistorius’s stride length was the same, but that his speed through the air was faster than that of an able-bodied athlete who participated in the same race.
The IAAF concluded that Pistorius’s Cheetah Flex-Foot running legs provide less air resistance than normal legs, a factor that could count in his favour.
The shape of the blades, which resembles a set of springs, could also be giving Pistorius an unfair advantage, according to Tucker.
“These blades are designed to store energy on landing, and then to return as much of the energy as possible – an action that propels Oscar forward,” Tucker says. “A pair of human legs can’t do that.”
Consider your own legs for a moment: if you jump off a table, you won’t bounce back – unless you actively invest some energy. But the opposite is true for Pistorius. “The Cheetahs bounce of their own accord,” Tucker says.
This brings us to the third factor.
When an able-bodied athlete runs, the muscles of the lower legs and feet have to contract before energy can be stored and used again. This process in itself utilises energy. So, for energy to be created there is a cost involved: a gradual loss of energy, which eventually leads to fatigue.
But Pistorius’s blades don’t require this type of energy as there are no muscles to contract. This means that the metabolic cost of running is lower for Pistorius, giving him “a potentially enormous advantage”, Tucker and Jonathan Dugas, also a sports scientist, writes on their The Science of Sport blog.
“With the Cheetahs, you’re actively adding energy,” Tucker says, which might explain why Pistorius becomes faster during the latter part of the race, while his opponents get slower.
The flipside of the coin
But Corné Rossouw, adapted physical activity specialist of the Department of Human Movement Science at the University of Stellenbosch, feels that Pistorius should get more credit.
“What is it that makes the prostheses move in the first place?” she asks. “While he doesn’t have calf muscles, it’s still his muscles that move him forward. The prostheses still need to be moved by the muscles in his upper legs. ”
In training, Pistorius’s coach would be focusing on strengthening these muscles, Rossouw says. “It’s important to remember that he doesn’t have an ankle or a workable knee... he basically runs by means of a hip action and has developed a different moving pattern altogether.”
She believes that Pistorius definitely has talent. “Unfortunately, none of us can really measure it.”
While Rossouw isn’t so outspoken on whether Pistorius has an unfair advantage or not, she believes that he will have to decide where he wants to participate: in able-bodied or in paraplegic events. “It has to be one or the other.”
Luck might have been on his side
Compared to other disabled athletes, Pistorius has, in a sense, been lucky.
He learnt to adjust to prostheses at an early age, he was in good medical care from the start, he is a double-leg amputee – which makes his balance better than that of a single-leg amputee – and he has been exposed to many opportunities. He is also fortunate enough to be running with a pair of the best prostheses available.
Both experts agree that difficult decisions will have to be made – by the athletic authorities and by Pistorius.
At some point, it seems that we would have to take a hard look at the difference between independent human performance and performance aided by artificial means, whether these be drugs, bionic limbs or simply a pair of state-of-the-art running shoes.
But whether Pistorius will be affected remains to be seen. – (Carine van Rooyen, August 2007)
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