Research by College of Charleston Biology Assistant Professor, Andrew Clark, shows that moving quickly across a slippery surface is less likely to lead to a fall than if you move slowly. His conclusions are published in the March 24, 2011 issue of the Journal of Experimental Biology, a leading journal in comparative animal physiology. Clark and Clemson University’s Timothy Higham (assistant professor of biology) found that major fall-avoidance strategies over low-friction surfaces are conserved across speeds and limbed terrestrial animals.
The researchers used high-speed video, kinetics and inverse dynamics to investigate the locomotor biomechanics of helmeted guinea fowl traversing slippery surfaces at variable running speeds. They found that falls were circumvented when limb contact angles exceeded 70 deg, though lower angles were tolerated at faster running speeds.
Generally, running faster over slippery ground is safer than running slower over slippery ground. Approaching the slippery surface slowly can preclude a forward shift of the body’s center of mass (COM) over the foot during ground contact. A forward shift of the COM is necessary for completing foot-ground contact phase during running or walking. Moreover, during contact with slippery ground, the forward shift of the COM limits the slip distance. Falls are prevented when slip distances are kept small (less than 10 cm). A slip distance threshold of 10 cm is also applicable to walking humans.
“Perhaps the most interesting result we found is that running guinea fowl use the same fall-avoidance strategies as walking humans and walking quadrupeds (four-legged animals),” Clark says. “This is an insightful model for invasive approaches to understanding limb neuromuscular control on slippery surfaces.”
Both Clark and Higham study biomechanics, and are interested in how animals move and avoid injury in their structurally complex and often dangerous worlds.
For more information, contact Andrew Clark at email@example.com or 949-394-6106