Related Experiment Video
Updated: Jun 6, 2026
07:52
Evaluating Postural Control and Lower-extremity Muscle Activation in Individuals with Chronic Ankle Instability
Published on: September 18, 2020
Dynamic stability of human walking in visually and mechanically destabilizing environments
Patricia M McAndrew1, Jason M Wilken, Jonathan B Dingwell
1Department of Biomedical Engineering, University of Texas, Austin, TX 78712, USA.
Journal of Biomechanics
|November 25, 2010
Summary
Perturbations to visual or support surfaces during walking reveal dynamic stability changes. Mediolateral disturbances caused greater instability, highlighting directional sensitivity in human balance control.
Area of Science:
- Biomechanics
- Human Locomotion
- Dynamic Stability
Background:
- Assessing dynamic stability is crucial for diagnosing fall risk in patients.
- Understanding human responses to perturbations informs the development of diagnostic tools.
Purpose of the Study:
- To investigate how continuous low-amplitude perturbations affect dynamic stability measures during walking.
- To determine if different perturbation types (visual, support surface) and directions (anterior-posterior, mediolateral) elicit specific stability changes.
Main Methods:
- Subjects walked in a virtual environment with optic flow while subjected to pseudo-random oscillations of the visual scene or support surface.
- Perturbations were applied in anterior-posterior and mediolateral directions.
- Measures of dynamic stability, including Floquet multipliers and local divergence exponents, were analyzed.
Main Results:
- Both Floquet multipliers and short-term local divergence exponents increased during perturbed walking, indicating greater instability.
- Responses were stronger when body movements aligned with perturbation directions.
- Mediolateral perturbations elicited greater sensitivity than anterior-posterior perturbations.
- Long-term local divergence exponents decreased, suggesting faster achievement of maximum divergence limits.
Conclusions:
- Continuous perturbations induce measurable changes in dynamic stability during walking.
- Human balance control exhibits directional sensitivity, with greater instability in the mediolateral direction.
- Different stability measures (Floquet multipliers, short-term/long-term divergence exponents) provide complementary insights into instability and adaptation during perturbed locomotion.
