By Gary Thomas
Blade Runners
How Are The Blades Made?
Even Better Than the Real
Thing?
Sources and Further Reading
Blade Runners
The Paralympic games are bigger than ever, with 4280 athletes
competing across 166 teams, and much new found media attention. A lot
of this attention can be attributed to the ‘blade runner’ from South
Africa, Oscar Pistorius, who is very much the poster boy for the
Paralympics.
The story of Pistorius is an undeniably inspiring one. He is a
double below-the-knee amputee, with both lower legs being taken at the
age of 11 months old. Rather than letting his disability limit him,
Oscar had his limbs replaced with ‘blades’, which not only allow him to
walk, but also run-fast! His notoriety was secured when this summer
Oscar Pistorius became the first disabled athlete to run in the Olympic
Games.
However, controversy has accompanied the South African ‘blade
runner’ with his increasing fame, with people across the globe debating
whether athletes using running blades should be allowed to compete in
the Olympics.
Further controversy raised its head several weeks ago, when Oscar
Pistorius suffered a shock defeat in the 200m T43/44 final at the hands
of Alan Fonteles Oliveira from Brazil. Pistorius was more than a little
disgruntled about the result, claiming that the length his rival’s
blades gave him an unfair advantage. Since this, other leading
paralympians have entered the debate regarding running blades. Jerome
Singleton, a single leg amputee from the United States, has voiced
concerns that athletes using two running blades could have an advantage
because of the length alterations they can make to the blades to suit
the race.
This article looks at the composition and manufacture of these
running blades to hopefully shed some light onto how they affect an
athlete’s performance. Below is a video from running blade manufacturer
Ottobock, displaying how a running blade can be used for athletics as
well as in everyday life.
How Are The Blades Made?
The running blades used by amputee athletes are an advanced type of
prosthesis, or prosthetic limb, which are used to replace a missing
body part.
In general, there are three main parts to a running blade:
- The blade itself
- A socket to attach the blade to the body
- An artificial knee joint (if required)
Invented in the 1970’s, the blades store kinetic energy in a similar
fashion to a spring which allows the athlete to run and jump. The
blades themselves are made from lightweight carbon fibre. Carbon fibre
is a resilient material that is stiffer than steel, and around five
times stronger. Stands of carbon fibre are twisted tightly together to
form a continuous layer, and these layers are then laid over the top of
each other to form the blade. Over 80 layers of carbon fibre are
required to make one running blade, and these need to be laid by hand.
The blades are the moulded by pressure and heat to fuse the layers
together and then this can be shaped into the final blade. These blades
can be customised to the athlete’s particular requirements.
The motion of running is replicated as closely as possible by the
blade – therefore the blades do not have a replica heel, as this is not
used in natural running. To assist with gripping the track, blades can
be fitted out with running spike, just like standard running shoes.
These can be troublesome to attach to the smooth carbon fibre blade and
are often attached by hand. The spikes used by Oscar Pistorius are
provided by Nike, in the form of a special ‘spike pad’, which is
affixed to the bottom of the blade. A pair of running blades can cost
around $5000 per pair.
Sgt. Jerrod Fields, a U.S. Army World Class Athlete Program Paralympic sprinter hopeful, works out at the U.S. Olympic Training Center in Chula Vista, Calif. A below-the-knee amputee, Fields won a gold medal in the 100 meters with a time of 12.15 seconds at the Endeavor Games in Edmond, Okla., on June 13, 2009. Image Credit: Tim Hipps, FMWRC Public Affairs
Even Better Than the
Real Thing?
One of the main debates involving prosthetic running blades is
whether they give the athlete an unfair advantage in a race.
Compared to a natural limb, this will not be the case. The idea of
the blades is to restore as much functionality to the runner as
possible, rather than to enhance abilities. There is no muscle power in
the limb itself, meaning that an athlete only has the power generated
by their hip flexor muscles and hamstrings. Furthermore, whilst a real
limb returns 250% of the energy stored, a running blade will return a
mere 90%.
A more important argument is whether the length of blade can make a
substantial difference to the performance of an athlete in a Paralympic
event. Many blade manufacturers argue that no two pairs of blades will
be the same, as no two athletes that use them are the same. The
different natural heights of athletes are used to determine the optimum
and most natural length of running blade for that particular athlete.
However the IPC has agreed that more research needs to be undertaken to
find out that exact effects of different types of running blades in
athletics.
This particular debate is destined to run and run, long after the
Paralympics have ended.
Sources and Further
Reading
http://passion.ottobock.com/en/technology/your-own-running-blade/
http://www.fastcodesign.com/1670487/how-nike-made-track-spikes-for-oscar-pistorius-s-carbon-fiber-blades
http://www.guardian.co.uk/sport/2012/sep/03/oscar-pistorius-rules-blades-paralympics
http://www.wired.co.uk/news/archive/2012-09/03/paralympic-technologies
http://passion.ottobock.com/fileadmin/_passion/user_upload/technology/Running_blades_used_by_Paralympic_athletes.pdf
http://www.paralympic.org/Events/London2012/AboutUs
http://www.standard.co.uk/olympics/olympic-news/running-on-blades-the-role-of-technology-in-paralympics-8104167.html
http://www.guardian.co.uk/sport/2012/sep/05/paralympics-running-blades-pistorius