To what extent does not wearing shoes affect the local dynamic stability of the gait? Effect size and intra-session repeatability

TL;DR

This study compares the local dynamic stability of gait between shod and barefoot walking in healthy individuals, finding minimal differences and high intra-session repeatability, supporting barefoot walking as a reliable assessment method.

Contribution

It provides evidence that barefoot walking does not significantly alter gait LDS and demonstrates high intra-session repeatability, validating its use in gait stability assessments.

Findings

Barefoot walking does not significantly change LDS compared to shod walking.

Intrasession repeatability is high for both walking conditions, slightly higher barefoot.

Barefoot walking can reliably evaluate gait stability without bias.

Abstract

Local dynamic stability (LDS) quantifies how a system responds to small perturbations. Several experimental and clinical findings have highlighted the association between gait LDS and fall risk. Walking without shoes is known to slightly modify gait parameters. Barefoot walking (BW) may cause unusual sensory feedback to individuals accustomed to shod walking (SW), and this may impact on LDS. The objective of this study was therefore to compare the LDS of SW and BW in healthy individuals and to analyze the intrasession repeatability. Forty participants traversed a 70 m indoor corridor wearing normal shoes in one trial and walking barefoot in a second trial. Trunk accelerations were recorded with a 3D-accelerometer attached to the lower back. The LDS was computed using the finite-time maximal Lyapunov exponent method. Absolute agreement between the forward and backward paths was estimated with the intraclass correlation coefficient (ICC). BW did not significantly modify the LDS as compared to SW (average standardized effect size: +0.12). The intrasession repeatability was high in SW (ICC: 0.73-0.79) and slightly higher in BW (ICC: 0.82-0.88). Therefore, it seems that BW can be used to evaluate LDS without introducing bias as compared to SW, and with a sufficient reliability.