Attenuated intersegmental cancellation compromises whole-body angular momentum control during perturbed locomotion

Area of Science:

• Biomechanics
• Human Movement Science
• Motor Control

Background:

• Whole-body angular momentum control is vital for stable locomotion.
• Segment-to-segment angular momenta cancellation is a key regulatory mechanism.
• Understanding this mechanism under various perturbations is crucial for gait stability.

Purpose of the Study:

• To investigate the segment-to-segment angular momenta cancellation during perturbed walking.
• To analyze the impact of different perturbations (unpredictable, adapted drop-like, hole negotiation) on this mechanism.
• To assess the role of experience in adapting intersegmental coordination.

Main Methods:

• Measured whole-body angular momentum and cancellation coefficients across sagittal, frontal, and transverse planes.
• Analyzed data from 18 participants during unperturbed walking and various perturbed conditions.
• Utilized motion capture and inverse dynamics to quantify angular momenta.

Main Results:

• Perturbed walking significantly increased whole-body angular momentum, especially during unpredictable perturbations.
• Cancellation coefficients decreased significantly in the sagittal plane across all perturbations.
• A significant decrease in the transverse plane was observed for unpredictable perturbations, while the frontal plane showed no significant changes.

Conclusions:

• Reduced intersegmental cancellation attenuates a key coordination mechanism during perturbed walking.
• Experience enhances intersegmental coordination, primarily in the transverse plane.
• The frontal plane exhibits limited regulatory capacity for whole-body angular momentum control via this mechanism.