# Asymmetry of short-term control of spatio-temporal gait parameters during treadmill walking

## TL;DR

This study investigates the short-term control mechanisms of gait parameters during treadmill walking, revealing asymmetries and leg dominance in how humans adapt step-to-step to perturbations at different speeds.

## Contribution

It provides new insights into the asymmetrical and speed-dependent nature of short-term gait control in healthy individuals.

## Key findings

- Right leg dominance in short-term control at higher speeds
- Interleg and intraleg control mechanisms identified
- Asymmetry in control of step duration, length, and speed

## Abstract

Optimization of energy cost determines average values of spatio-temporal gait parameters such as step duration, step length or step speed. However, during walking, humans need to adapt these parameters at every step to respond to exogenous and/or endogenic perturbations. While some neurological mechanisms that trigger these responses are known, our understanding of the fundamental principles governing step-by-step adaptation remains elusive. We determined the gait parameters of 20 healthy subjects with right-foot preference during treadmill walking at speeds of 1.1, 1.4 and 1.7 m/s. We found that when the value of the gait parameter was conspicuously greater (smaller) than the mean value, it was either followed immediately by a smaller (greater) value of the contralateral leg (interleg control), or the deviation from the mean value decreased during the next movement of ipsilateral leg (intraleg control). The selection of step duration and the selection of step length during such transient control events were performed in unique ways. We quantified the symmetry of short-term control of gait parameters and observed the significant dominance of the right leg in short-term control of all three parameters at higher speeds (1.4 and 1.7 m/s).