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Angelika Hofstetter
12-03-1998, 10:44 PM
Dear Biomechanic-List

About one weeks ago, I posted a request about ground reaction forces.
I would like to thank all the people who responded and expressed interest.

The request was the following:
I am interested in GRF in normal walking humans. My literature search was
not very profitable. There are many studies on GRF, but mainly the vertical
and sagittal components of the forces are investigated, and the connection
with walking speed. In particular, I investigate if there are sex
differences, and I found that the medio-lateral force component is
promising to discriminate the the walking of men and women.
I would be grateful for some references or hints.

Summary of answers and ideas:
1. The medio-lateral component of the GRF is the smallest and the most
variable (intra- and interindividual) of the three components.
For example, Giakas & Baltzopoulos (1997 - reference see in the mail below)
say, that selected time domain parameters in the medial-lateral direction,
especially during pronation, contain substantial variabilty and they should
not be used as criterion for normal gait.
Conclusion: Fmedio-lateral too small and variable to give reliable results.
2. But in the meantime, I found some literature myself, that also gives sex
specific differences in GRF (e.g. Chao EY, Laughman RK, Schneider E &
Stauffer RN (1983) Normative data of knee joint motion and ground reaction
forces in adult level walking. J Biomechanics 16: 219-233.).
Comparing the different studies that I found, I think it depends on the
number of subjects in the study: small number of subjects - no differences,
greater number - sex differences detected. Maybe, the interindividual
differences cover the sex related differences in a statistical analysis, if
there are only a small number of subjects.
And I found a study, where the minimum of Fmedio-lateral was the variable
to seperate normals and knee patients (Andriacchi TP, Ogle JA & Galante JO
(1977) Walking speed as a basis for normal and abnormal gait measurements.
J Biomechanics 10: 261- 268.).

Additional comments and ideas on that are very welcome!

Following some original mails:

Giannis Giakas PhD
Sport Health and Exercise, School of Health, Staffordshire University
http://www.staffs.ac.uk/health/sport/giannis/index.htm
Check the following paper
Giakas G and V Baltzopoulos (1997). Time and Frequency domain analysis of
ground reaction forces during walking: an investigation of variability and
symmetry. Gait and posture 5, 189-197.
Frequency domain analysis might give something interesting there.

Dr. Axel Knicker
Deutsche Sporthochschule Köln
http://www.dshs-koeln.de/
Die Bodenreaktionskraft ist Ausdruck der Interaktion zwischen dem
Menschlichen Körper und der Erdmasse. Somit sind die Reaktionskraftwerte
immer bezogen auf den Körperschwerpunkt des menschlichen Körpers. Sie
ist abhängig von der Masse des Probanden und dessen Beschleunigung
während der Bewegung. Aus diesen Gründen sind geschlechtsspezifische
Unterschiede der auftretenden Kräfte beim Gehen mit vergleichbaren
Ganggeschwindigkeiten nicht zu erwarten. Ein mehr oder weniger
ausgeprägter Kraftverlauf in med.lat. Richtung hätte eine entsprechend
ausgeprägte KSP Bewegung zur Folge. Nach meiner eigenen Abschätzung sind
die geschlechtsspezifischen KSP Seitbewegungen während des normalen
Gehens so gering, daß eine Differenzierung schwierig (nicht reliabel)
ist. Anders sieht es vielleicht aus, wenn Sie Laufsteg-Gehen mit
normalem Gehen (bei gleicher Geschwindigkeit) vergleichen wollten. Doch
auch da sind geschlechtsspezifische Unterschiede nicht zu erwarten, es
sei denn, Sie vergleichen Männer auf dem Laufsteg mit Frauen im normalen
Gehen.
English short summery: GRF are related to the movement of the center of
mass of the human body in relation to the mass and the velocity of the
subject. Therfore no sex differences are expected during walking with
similar speed. The lateral movement of the COM are very small, so the
differences in the medio-lateral force component will not be reliable.

Jeremy Linskell
Manager, Gait Analysis Laboratory
Co-Ordinator, Electronic Assistive Tehcnology Service
http://www.dundee.ac.uk/orthopaedics/dlfc/gait.htm
I think that you will find that the Medio-Lateral GRF differfences
between men and women are due to the difereing pelvic geometries in
these two groups, but I am afraid that I do not have any specific
refences which support this view.

Gaspar Morey Klapsing
INSTITUTE FOR ATHLETICS AND GYMNASTICS
SPORTS UNIVERSITY COLOGNE
http://www.dshs-koeln.de/turnen/instgerp.htm
Human Kinetics hat schon vor einiger Zeit eine Software veröffentlicht in der
typische GRF während des Ganges dargestellt werden. Wenn ich mich nicht
täusche
gibt es auch die Option Mann oder Frau zu wählen. Wenn auch die Software
selbst
nicht unbedingt viel bringt, kann vielleicht die Autorin etwas dazu erzählen.
English short summary: Human Kinetics published a software (gait lab from
Kit Vaughan, Brian Davis & Jeremy O’Connor) with typical GRF. There is an
option to choose the gait of a man or a woman. Maybe this software or the
author can help you.

Anamaria Siriani de Oliveira from ufscar in Brasil
Do you know Laboratório de Biomecânica - USP-EEFE?
Homepage - http://www.usp.br/eef/eefusp.htm



******************************************
Angelika M. Hofstetter, Dipl.Biol.
Anthropologie u. Humanbiologie
Freie Universitaet Berlin
Fabeckstr. 15, 14195 Berlin, Germany
Fon +49 (0)30 838 2902
Fax +49 (0)30 838 6556
*****************************************

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