Does increased gait variability improve stability when faced with an expected balance perturbation during treadmill...

Area of Science:

• Biomechanics
• Human movement science
• Motor control

Background:

• Movement variability is crucial for adaptability but its role in error detection or exploration remains unclear.
• Understanding variability's function is key to developing effective interventions for balance disorders.

Purpose of the Study:

• To investigate if gait variability serves as an exploratory mechanism to enhance stability.
• To test if spatiotemporal gait features increase before a perturbation and if this correlates with improved post-perturbation stability.

Main Methods:

• Healthy adults walked on a treadmill in a motion simulator under unperturbed and expected perturbation conditions.
• Kinematic data analyzed step length, width, and time variability before and during perturbations.
• Stability was quantified by the number of steps to center of mass restabilization post-perturbation.

Main Results:

• Long-term step width variability significantly increased prior to an expected perturbation compared to unperturbed walking.
• No significant differences were found in step length or time variability between conditions.
• Pre-perturbation variability did not significantly correlate with post-perturbation stability.

Conclusions:

• Increased step width variability before a perturbation indicates an exploratory strategy in anticipation of balance challenges.
• This exploratory gait adjustment did not demonstrably improve or impair stability in healthy young adults.