View Full Version : Normalizing force plate results

David Davis
02-09-1997, 08:27 PM
Dear All,

I hope that someone may be able to help / put me straight. I am currently
working on gait analysis during load carraige. This involves subjects of
differing sizes , with differing loads free speed walking over a force plate
and recording the results.
Now in order to accurately compare the results I at first thought that
expressing the forces as a percentage of body weight / total weight was
best. But it occurred to me that with free speed walking, intrasubject
variation of velocities as well as intersubject variation of velocities
occurred and (this is the bit that concerns me) since velocity is a factor
of acceleration and acceleration is a factor of force, are not the ground
reaction forces affected by velocity changes. Or do we safely assume that
during terminal swing the only acceleration acting is gravity??

I hope someone can explain a method of normalizing for this or at least tell
me of an experimental protocol that avoids this or tell me I'm wrong!!!! , I
will post a summary of replies.

Thanks in advance

David Davis
Department of Human Sciences
Loughborough University
LE11 3TU
Tel: 01509 223086
Fax: 01509 223941
Email: D.Davis@lboro.ac.uk