PDA

View Full Version : Pose Running



nbrown44
11-13-2008, 03:08 PM
We were interested in the recent post on Pose running and would like to try and spark a discussion on the topic. In no way are we trying to support or discount the possibility that the Pose method improves running technique by increasing speed or reducing injury.

In Dr Romanov's discussion paper on the Pose running technique (Romanov and Fetcher, 2007, Sport Biomechanics, 6, pp434-452), the authors state that they "hope to establish theoretically that gravity is the motive force in running...". The paper then argues from this perspective that other motive forces such as from muscles are relatively unimportant. The forces that act on the human body in motion include; (i) motion-dependent forces (from Coriolis and inertial effects), (ii) internal forces (principally from muscle), (iii) external forces (from ground, wind etc), and (iv) forces due to gravitational acceleration. Well-coordinated movement has also been shown to be characterized by the ability to adjust muscular forces to account for or to take advantage of motion-dependent, gravitational and external forces (e.g. Hollerbach et al 92; Schneider et al, 89 & 90; Ulrich et al 94). Running is likely no different from other well-coordinated body movements in that the runner or mover must account for and exploit the force environment in which they find themselves.

While gravitational acceleration might be particularly important in running, the external, motion-dependent and muscular forces can not be discounted as contributing to forward acceleration of the body. Zajac, Neptune and Kautz (2002, Gait and Posture, 17, pp1-17) review nicely how forward trunk acceleration receives marked contributions from lower extremity muscles, at least in walking. Romonov and Fetcher (2007) also state that extensor muscle activity ceases during mid stance and an extensor paradox arises. We have EMG on numerous good runners (national and international level) at running speeds of 6 to 9 m/s and we find ample EMG activity in late stance from muscle throughout the limb, including extensor muscles. Even without extensor muscles being active (which some are) forward acceleration of the trunk can arise from these 'non-extensor' muscles, although the magnitude of their contribution appears to be unknown for faster running.

It is certainly interesting to consider how good runners might exploit motion-dependent and gravitational forces (perhaps the Pose Technique promotes this), and how various muscles of the lower extremity contribute to the forward acceleration of the body's mass centre.

We would be interested in the thoughts of others.

Doug Rosemond, John Baker, Wayne Spratford, Alexi Sachlikidis, Sara Brice, Nick Brown
Department of Biomechanics and Performance Analysis
Australian Institute of Sport
Canberra, Australia


-------------------------------------------------------------------------------------
Keep up to date with what's happening in Australian sport visit http://www.ausport.gov.au

This message is intended for the addressee named and may contain confidential and privileged information. If you are not the intended recipient please note that any form of distribution, copying or use of this communication or the information in it is strictly prohibited and may be unlawful. If you receive this message in error, please delete it and notify the sender.
-------------------------------------------------------------------------------------