An investigation into the ergonomics of standing

Whistance, Rosemary Simpson

An investigation into the ergonomics of standing

Thesis / Dissertation

1996

Publisher

University of Cape Town

Department

Division of Biomedical Engineering

Faculty

Faculty of Health Sciences

Abstract

This section examines the literature on standing and attempts to build up a comprehensive picture of what happens when a human being stands upright. The review starts by exploring those changes to the skeleton and musculature which have enabled homo sapiens to be erect. This is followed by a look at how humans maintain upright posture through postural control and the role of the 'anti-gravity muscles'. Postural sway is inherent to standing and this is examined in some detail along with the concepts of centre of foot pressure and effective foot base. Attention is drawn to the fact that the subtleties of the upright posture_ are largely determined by culture and background. Foot position largely determines the quality of upright posture and this concept is explored in some detail. There are quantifiable physiological changes which occur when going from a supine position to an upright position and the review covers a comprehensive examination of these. In addition, the phenomenon of postural stress is also discussed. Besides postural sway, people move while standing and various reasons for changing postures are presented. The review also examines asymmetry, an inherent aspect of standing. Finally, research on standing in the wor~place is discussed. It is clear that the area is under-researched. Much work on standing was done earlier in the early part of the century and then again 40 and 50 years ago. Very little of this early research has penetrated ergonomics. By contrast, there is a vast body of accepted research on seating which is applied in ergonomics. This review seeks to present knowledge about standing which may be applied in the context of ergonomics. The preceding review underscores the importance of focusing on the standing worker who must simultaneously contend with multiple variables like gravity, culture, workplace constraints, physiological changes and bodies which have not evolved for many of the postures imposed on them.