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Updated: Jul 11, 2026
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A Training Program Using an Agility Ladder for Community-Dwelling Older Adults
Published on: March 7, 2020
Zigzagging: theoretical insights on climbing strategies.
1Department of Anthropology, University of Washington, Denny 32, Box 353100, Seattle, WA 98195-3100, USA. mllobera@u.washington.edu
Journal of Theoretical Biology
|September 26, 2007
Summary
Humans adopt switchbacks and shortcuts on steep terrain to minimize energy expenditure. This theoretical model explains trail formation, showing direct paths on gentle slopes and switchbacks on steeper inclines for efficient movement.
Area of Science:
- Biomechanics
- Theoretical Physics
- Human Geography
Background:
- Human and animal trails on steep hillsides often feature switchbacks and shortcuts.
- Previous research examined trail systems on flat terrain and the effect of gradients on human metabolic efficiency.
Purpose of the Study:
- To develop a semi-quantitative theoretical model for human movement on varied terrain.
- To explain the emergence of switchbacks and shortcuts in human trail systems.
Main Methods:
- Developed a model minimizing metabolic cost per unit distance.
- Utilized principles similar to the Landau Theory of Phase Transitions.
- Analyzed movement strategies for uphill and downhill walking on different slopes.
Main Results:
- Both switchbacks and shortcuts are efficient for downhill movement; switchbacks are retained for uphill movement.
- Direct uphill/downhill walking is optimal on gentle slopes.
- Steeper slopes trigger a transition to switchback patterns, with a lower critical slope for downhill than uphill movement.
Conclusions:
- The model predicts efficient human movement strategies, explaining trail patterns in rugged environments.
- The theory provides a framework for generalizing previous work to real landscapes.
- The model has potential applications in reconstructing ancient movement patterns in archaeological landscapes.
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