Effect of voluntary periodic muscular activity on nonlinearity in the apparent mass of the seated human body during vertical random whole-body vibration


Huang, Ya and Griffin, Michael J., Griffin, Michael J. and Bovenzi, Massimo (eds.) (2006) Effect of voluntary periodic muscular activity on nonlinearity in the apparent mass of the seated human body during vertical random whole-body vibration. Journal of Sound and Vibration, 298, (3), 824-840. (doi:10.1016/j.jsv.2006.06.028).

Download

Full text not available from this repository.

Description/Abstract

The principal resonance frequency in the driving-point impedance of the human body decreases with increasing vibration magnitude—a nonlinear response. An understanding of the nonlinearities may advance understanding of the mechanisms controlling body movement and improve anthropodynamic modelling of responses to vibration at various magnitudes. This study investigated the effects of vibration magnitude and voluntary periodic muscle activity on the apparent mass resonance frequency using vertical random vibration in the frequency range 0.5–20 Hz. Each of 14 subjects was exposed to 14 combinations of two vibration magnitudes (0.25 and 2.0 m s−2 root-mean square (rms)) in seven sitting conditions: two without voluntary periodic movement (A: upright; B: upper-body tensed), and five with voluntary periodic movement (C: back-abdomen bending; D: folding-stretching arms from back to front; E: stretching arms from rest to front; F: folding arms from elbow; G: deep breathing). Three conditions with voluntary periodic movement significantly reduced the difference in resonance frequency at the two vibration magnitudes compared with the difference in a static sitting condition. Without voluntary periodic movement (condition A: upright), the median apparent mass resonance frequency was 5.47 Hz at the low vibration magnitude and 4.39 Hz at the high vibration magnitude. With voluntary periodic movement (C: back-abdomen bending), the resonance frequency was 4.69 Hz at the low vibration magnitude and 4.59 Hz at the high vibration magnitude. It is concluded that back muscles, or other muscles or tissues in the upper body, influence biodynamic responses of the human body to vibration and that voluntary muscular activity or involuntary movement of these parts can alter their equivalent stiffness

Item Type: Article
Additional Information: Special Issue on the Third International Conference on Whole-body Vibration Injuries, Nancy, France, 07-09 Jun 2005
ISSNs: 0022-460X (print)
Related URLs:
Subjects: T Technology > TA Engineering (General). Civil engineering (General)
Q Science > QP Physiology
Divisions: University Structure - Pre August 2011 > Institute of Sound and Vibration Research > Human Sciences
ePrint ID: 45639
Date Deposited: 13 Apr 2007
Last Modified: 27 Mar 2014 18:29
URI: http://eprints.soton.ac.uk/id/eprint/45639

Actions (login required)

View Item View Item