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Adrian Smith
01-15-2008, 08:07 PM
The IAAF announcement is at:

http://www.iaaf.org/news/Kind=512/newsId=42896.html

I quote:

- Analysis was carried out by a team of more than 10 scientists,
including staff from the physiology laboratory of Professor J. Mester
(Institute of Training Science and Sport Informatics).

- 12 high speed cameras (250 frames per second) were used to record 3D
kinematics, with another 4 highspeed cameras to observe sagittal plane
motion

- Force platforms were used to record ground reaction forces and point
of force application

- Athletes ran the 400m test with a K4 mask to record max VO2. VO2
testing was also carried out in the laboratory (Wingate and Ramp Test)
on static bicycles. Blood lactate records were taken regularly

- A 3D scanner was used to record body mass and anthropometric measures
of all the control athletes

- The prosthetics were also subjected to material testing

---------

The objective results of this study are that:

- Pistorius was able to run with his prosthetic blades at the same speed
as the able-bodied sprinters with about 25% less energy expenditure. As
soon as a given speed is reached, running with the prosthetics needs
less additional energy than running with natural limbs.

- Once the physiological potential of Oscar Pistorius and the
able-bodied control athletes had been estimated, using three different
methods, it is clear that Pistorius' potential was not higher than that
of the controls, even though their performance results were similar.

- The biomechanical analysis demonstrated major differences in the
sprint mechanics used by a below-knee amputee using prosthetics when
compared to athletes with natural legs. The maximum vertical ground
reaction forces and the vertical impulses are different in a highly
significant way and the amount of energy return of the prosthetic blade
have never been reported for a human muscle driven ankle joint in sprint
running.

- The positive work, or returned energy, from the prosthetic blade is
close to three times higher than with the human ankle joint in maximum
sprinting.

- The energy loss in the prosthetic blade was measured at 9.3% during
the stance phase while the average energy loss in the ankle joint of the
able bodied control athletes was measured at 41.4%. This means that the
mechanical advantage of the blade in relation to the healthy ankle joint
of an able bodied athlete is higher than 30%.

"It is evident that an athlete using the Cheetah prosthetic is able to
run at the same speed as able bodied athletes with lower energy
consumption. Running with prosthetic blades leads to less vertical
motion combined with less mechanical work for lifting the body. As well
as this, the energy loss in the blade is significantly lower than in the
human ankle joints in sprinting at maximum speed. An athlete using this
prosthetic blade has a demonstrable mechanical advantage (more than 30%)
when compared to someone not using the blade.

"IAAF Council has been able to review the full report and has decided
that the prosthetic blades known as "cheetahs" should be considered as
technical aids in clear contravention of IAAF Rule 144.2. As a result,
Oscar Pistorius is not eligible to compete in competitions organised
under IAAF Rules.



-------

Adrian Smith
Headingley UK
+44 (0)113 3435531


-----Original Message-----
From: * Biomechanics and Movement Science listserver
[mailto:BIOMCH-L@NIC.SURFNET.NL] On Behalf Of Rodger Kram
Sent: 15 January 2008 21:49
To: BIOMCH-L@NIC.SURFNET.NL
Subject: [BIOMCH-L] Bruggemann report

I have tried in vain to find the Bruggemann report on Oscar Pistorius
and elastic energy storage in his prosthetic legs.

Can anyone provide a link?

I'd like to discuss the findings that have been leaked to the press but
I think that as a scientist it is only fair to wait and read the full
report.

thanks
Rodger Kram, Ph.D.
Locomotion Lab
Integrative Physiology Dept.
University of Colorado, Boulder
USA
rodger.kram@colorado.edu