Abstract
Obstructions within a task environment provide opportunities for people to brace themselves with the non-task hand, thigh, or other body part. Previous research has shown that bracing can increase one-hand isometric force-exertion capability in standing tasks. The current laboratory study examined the patterns of force on the bracing surfaces as a function of task and human characteristics. Twenty-two men and women exerted static forces with their right hands. Bracing opportunities were provided at the thigh, contralateral hand, or both. Using the task hand force as a reference, bracing forces were decomposed into opposing and non-opposing components and normalised relative to task hand force magnitude. Five distinct patterns of bracing force, termed force-generation strategies (FGSs), emerged.
Additional information
Notes on contributors
Monica L.H. Jones
Monica L. H. Jones earned her PhD in industrial and operations engineering at the University of Michigan, and is currently a postdoctoral research fellow at Canada Defence Research and Development Centre in Toronto, Ontario.
Matthew P. Reed
Matthew P. Reed is a research professor and head of the Biosciences Group of the University of Michigan Transportation Research Institute. He is also the director of the Human Motion Simulation Laboratory in the Center for Ergonomics at the University of Michigan.
Don B. Chaffin
Don B. Chaffin is a Richard G. Snyder Distinguished University Professor Emeritus at the the University of Michigan. He is also the director emeritus of both the Human Motion Simulation Laboratory and the Center for Ergonomics at the University of Michigan.