Announcement

Collapse
No announcement yet.

Re: Bruggemann report

Collapse
This topic is closed.
X
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Re: Bruggemann report

    I see Pistorius is appealing the IAAF decision:
    http://www.theaustralian.news.com.au/story/0,25197,23063851-2722,00.html

    I still wonder about these statements in the report:

    - 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%*.
    How is it possible to measure "returned energy" in a
    normal foot/ankle? Absorption of energy is straightforward, and it's obvious
    that any subsequent positive energy from a prosthesis would have to be
    returned energy. Can anyone suggest how it would be possible to seperate how
    much energy is returned in the intact normal foot/ankle from that generated
    by the plantarflexors?

    Chris

    On 1/16/08, Adrian Smith wrote:
    >
    >
    >
    >
    > 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
    >
    > ---------------------------------------------------------------
    > Information about BIOMCH-L: http://www.Biomch-L.org
    > Archives: http://listserv.surfnet.nl/archives/Biomch-L.html
    > ---------------------------------------------------------------
    >
    > ---------------------------------------------------------------
    > Information about BIOMCH-L: http://www.Biomch-L.org
    > Archives: http://listserv.surfnet.nl/archives/Biomch-L.html
    > ---------------------------------------------------------------
    >



    --
    Dr. Chris Kirtley MB ChB, PhD
    608 Dockside
    44 Ferry St.
    Kangaroo Point
    Queensland 4169
    Australia
    Tel. (07) 3891 6644 x 1608
    Fax 3891 6900

    West End Family Medical Centre
    Wednesdays & Fridays (07) 3844 4111

    Clinical Gait Analysis: http://www.univie.ac.at/cga
    Book:
    http://www.amazon.co.uk/exec/obidos/ASIN/0443100098/203-6674734-4427132
Working...
X