Model proves efficiency of zigzagging

U.S. and British researchers have created a mathematical model demonstrating a zigzag course is the most efficient way for humans to climb steep slopes.

The study by Professors Marcos Llobera of the University of Washington and T.J. Sluckin of the University of Southampton show the course of a trail or path on a steep slope depends upon the energy costs of ascending and descending.

I think zigzagging is something people do intuitively, said Llobera. "People recognize that zigzagging, or switchbacks, help, but they don't realize why they came about.

There is a point, or critical slope, where it becomes metabolically too costly to go straight ahead, so people move at an angle, cutting into the slope. Eventually they need to go back toward the direction they were originally headed and this creates zigzags. The steeper the slope, the more important it is that you tackle it at the right angle.

In future work, Llobera plans to build a simulation engine that would allow archaeologists to plot a terrain and explore patterns of movement through it.

The study appears in the Journal of Theoretical Biology

Copyright 2008 by United Press International