Rethinking margin of stability: Incorporating step-to-step regulation to resolve the paradox.

ABSTRACT: Derived from inverted pendulum dynamics, mediolateral Margin of Stability (MoS_ML) is a mechanically-grounded measure of instantaneous frontal-plane stability. However, average MoS_ML measures yield paradoxical results. Gait pathologies or perturbations often induce larger (supposedly "more stable") average MoS_ML, despite clearly destabilizing factors. However, people do not walk "on average" - they walk (and sometimes lose balance) one step at a time. We assert the paradox arises because averaging MoS_ML discards crucial step-to-step dynamics. We present a framework unifying the inverted pendulum with Goal-Equivalent Manifold (GEM) analyses. We identify in the pendulum's center-of-mass dynamics constant-MoS_ML manifolds, including one can

SUBMITTER: Kazanski ME 

PROVIDER: S-EPMC10474615 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature