The available prosthetics were basic and uncomfortable, severely restricting his movement. For over a decade, he could not run.
"The legs were too heavy and manufacturing companies didn't understand what materials I needed," Lewis recalls.
Now 31, Lewis is fresh from winning a gold medal at the Madrid World Paratriathlon in September. The achievement owes much to his determination to succeed, but technology has also finally caught up with his ambition.
Lewis won the race using an Ottobock S380 - the first above-the-knee prosthetic leg specially made for athletes. A lightweight, shock-absorbing frame allows for greater speed and comfort, and a flexible knee joint provides range of movement and versatility that enables Lewis to make rapid transitions from the pool to bike to track -- which shaved critical seconds off his winning time.
But when we meet at his training center in Chesham, on the outskirts of London, the champion is impatient for further progress.
"By the Paralympics in 2016 I can envisage a lot of new legs coming out...The knees are getting smaller, the legs will have microprocessors, and you will be able to press a button to change foot for the different events."
Lewis also hopes to have a 3D-printed socket to avoid some of the bruising he suffers in competition.
To his support team at Pace Rehabilitation
, the new champion is a symbol of a revolution in prosthetics, which is transforming lives and sporting competition.
"There have been major changes in the last two to three years," says Pace's head prosthetist Jamie Gillespie. "It used to be that there were only two types of running blade, but companies are now offering a greater range for different competitions, adjusted to boost performance, so the challenge now is to find the right blade for the right person for the right sport."
Previous models were generally too painful for athletes with prosthetics to run over 200 meters, but Gillespie notes that Oscar Pistorius rose to prominence at 400 meters. As the possibilities multiply for disabled athletes, so too does participation, competition, and standards, which encourages manufacturers to develop ever-better equipment.
Pace's clients include numerous Paralympic athletes, and they work with some of the most advanced new prosthetics. These include Ottobock's new Genium X3
, widely regarded as the most advanced prosthetic leg in the world, co-developed with the US military and fitted with a micro-processor that adjusts for the user's stride pattern, different types of movement from jogging to climbing stairs, and a range of terrains.
Another client, skier Jozef Metelka, became the first European to receive a power assisted ankle system from Biom last year, which allows him to move faster and use less energy.
As the equipment improves, athletes with prosthetics have achieved some startling feats, even out-performing able-bodied athletes. Amputee long jumper Markus Rehm won the German national championships with a jump of 8.24 meters on carbon fiber blades, before the athletics federations controversially excluded him from their squad, claiming he could have an unfair advantage.
Sports engineer David James of the University of Sheffield Hallam sees the integration of technology in sport as inevitable, albeit disruptive.
"The issue is whether technology is enabling or enhancing," says James. "There is potentially so much technology that could be used, but even if an athlete is less responsible, competition could still be valid."
"Technology often defines sport -- windsurfing came out of sailing, snowboarding came out of skiing. People were horrified by full-body swimsuits at first. What starts as an aberration becomes accepted and respected in its own right. Sports do change, evolve and die out all the time."
The Paralympics is among the limiting factors for enhancements, as the authority's strict classifications designed to create level playing fields prohibit all but the most necessary equipment. As a result, basketball players and weightlifters cannot stand up even if they are able. As the main source of funding for athletes with disabilities, Paralympic rules often determine competitors' choice of prosthetics and much of their everyday lives.
There is frustration among athletes, but also fears that a liberal approach to enhancements would prove controversial. Double amputees are increasingly running faster than single counterparts as neither leg tires and they can take longer strides, creating a potential incentive to have both removed.
Similar dilemmas and possibilities are already established in able-bodied sport. Baseball pitchers have long relied on 'Tommy John Surgery
' to allow a fresh replacement of the key ulnar nerve in their throwing arms.
Athletes wishing to escape Paralympic rules have new options, such as the 2016 Cybathlon
-- the first 'robot-assisted Olympics.' Events will include powered wheelchair and powered exoskeleton races, and a competition driven by Brain-Computer Interface (BCI). Spectacular times could be posted, which the organizers are hoping for.
"If there is no danger I am happy for them to go beyond the limits of able-bodied athletes," says Cybathlon event director Robert Riener, a systems engineer at the Federal Institute of Technology, Zurich. "The devices could allow a paralyzed athlete to do better in a single function."
Over 70 teams have already applied to compete, says Riener, and the event is also expected to attract a global audience with the promise of technology and athletic competition adding up to a radical new form of sport.
Ultimately the aim of Cybathlon is to develop technologies for everyday use that improves quality of life for people suffering from debilitating conditions. But the concept of assisted sport is already expanding, with suggestions of robot-assisted events
at the 2020 Japan Olympics.
Futurists clamour for the old rules and distinctions to be cast aside, in order to allow free rein to creative solutions that could empower the disadvantaged and take competition into a radical new era. Tradition may have to succumb to unleash the full power of prosthetics.
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