Original URL: http://www.theregister.co.uk/2009/11/18/artificial_legs_better_than_real_ones/

High-tech 'blade runner' legs better than real ones - profs

Olympic ban on Dr Who Cybermen seems likely

By Lewis Page

Posted in Science, 18th November 2009 11:19 GMT

The argument over the use of artificial legs to gain better results in athletics has taken a new turn. Following lengthy legal debates, it had been accepted that prosthetic legs confer no substantial advantage, but now the very scientists who argued that case have changed their minds.

Today's new findings come from human-performance specialists Peter Weyand and Matthew Bundle, who had supported the appeal by famous double-amputee sprinter Oscar Pistorius against being banned from competing in the Olympics alongside able-bodied runners.

Lawyers for Pistorius, supported by Weyand and Bundle's arguments, were able to get the Olympic ban overturned in May 2008. As it turned out the "fastest man on no legs" failed to qualify for the South African squad that went to Beijing, as there were able-bodied runners who beat his times. However Pistorius has said that he hopes to try again for London in 2012 - when he will be 25, entering what should be his peak years as a sprinter.

Today's announcement from Weyand and Bundle would seem to cast doubt on those hopes, however, as the two experts now say that the evidence reviewed at the time of the 2008 decision was incomplete. They now believe that in fact Pistorius' high-tech "Cheetah" lower limbs confer a substantial advantage, taking as much as ten seconds off the 400m time he would achieve if he had intact limbs.

"We are pleased to finally be able to go public with conclusions that the publishing process has required us to keep confidential until now. We recognized that the blades provide a major advantage as soon as we analysed the critical data more than a year and a half ago," said Weyand and Bundle in a statement issued today.

The two biomechanics profs say that Pistorius' lightweight "blade" legs - which have given him the nickname "blade runner" - allow him to achieve a given speed while applying 20 per cent less ground force than an intact-limb runner would have to. He can also reposition his legs for another stride much more easily, and does so "15.7 per cent more rapidly than five of the most recent former world-record holders in the 100-meter dash".

According to Weyand and Bundle, the Cheetah blades "reduce the muscle forces Pistorius requires for sprinting to less than half of intact-limb levels".

The profs' volte-face would seem to raise the likelihood of the former ban on Pistorius competing at the Olympics being renewed, dashing his hopes for non-Paralympic glory at London in 2012.

That, of course, remains to be seen. In the meantime the profs' arguments - supporting as they do the idea that technological replacements are already superior to parts of the human body - would seem to foretell a future where people may begin to voluntarily replace unsatisfactory bits of themselves.

The advent of real-life Dr Who Cybermen has just come a step - or a sprint - closer.

Weyand and Bundle's new analysis is published tomorrow in the Journal of Applied Physiology. ®