Efficiency and Stability of Step-To Gait in Slow Walking.

Kento Hirayama,Toru Takahashi,Yutaka Tomita,Seigo Inoue,Kaoru Honaga,Yohei Otaka,Taichi Kurayama,Kunitsugu Kondo,Rieko Osu

doi:10.3389/fnhum.2021.779920

Abstract

As humans, we constantly change our movement strategies to adapt to changes in physical functions and the external environment. We have to walk very slowly in situations with a high risk of falling, such as walking on slippery ice, carrying an overflowing cup of water, or muscle weakness owing to aging or motor deficit. However, previous studies have shown that a normal gait pattern at low speeds results in reduced efficiency and stability in comparison with those at a normal speed. Another possible strategy is to change the gait pattern from normal to step-to gait, in which the other foot is aligned with the first swing foot. However, the efficiency and stability of the step-to gait pattern at low speeds have not been investigated yet. Therefore, in this study, we compared the efficiency and stability of the normal and step-to gait patterns at intermediate, low, and very low speeds. Eleven healthy participants were asked to walk with a normal gait and step-to gait on a treadmill at five different speeds (i.e., 10, 20, 30, 40, and 60 m/min), ranging from very low to normal walking speed. The efficiency parameters (percent recovery and walk ratio) and stability parameters (center of mass lateral displacement) were analyzed from the motion capture data and then compared for the two gait patterns. The results suggested that step-to gait had a more efficient gait pattern at very low speeds of 10–30 m/min, with a larger percent recovery, and was more stable at 10–60 m/min in comparison with a normal gait. However, the efficiency of the normal gait was better than that of the step-to gait pattern at 60 m/min. Therefore, step-to gait is effective in improving gait efficiency and stability when faced with situations that force us to walk slowly or hinder quick walking because of muscle weakness owing to aging or motor deficit along with a high risk of falling.

Highlights

People change their walking speed depending on situations (Leroux et al, 2002); they walk slowly when external environments are unstable, such as on slippery ice, or when internal environments are deficient in walking quickly, for example, weakened muscle owing to aging or motor deficit
The tests of the simple main effect of the gait patterns revealed that the percent recovery was significantly larger for the step-to gait pattern than for the normal gait at 10 m/min, 20 m/min, and 30 m/min (P < 0.01), while it was significantly smaller for the step-to gait pattern than for the normal gait at 60 m/min (P = 0.012)
For the normal gait pattern, multiple comparisons showed a significant difference between all speed conditions (P < 0.01)

Summary

Introduction

People change their walking speed depending on situations (Leroux et al, 2002); they walk slowly when external environments are unstable, such as on slippery ice, or when internal environments are deficient in walking quickly, for example, weakened muscle owing to aging or motor deficit In such cases, they can walk slowly with a normal gait pattern, or they can change their gait. Murakami et al reported that this walk ratio was constant when the walking speed was moderate or fast but gradually increased when the speed was less than approximately 62 m/min They suggested that the efficiency is not optimized in a slow or normal gait (Murakami and Otaka, 2017). They reported that the margin of stability decreased with a decrease in speed, concluding that the lateral stability of normal gait decreased at low speeds, especially at extremely low speeds (Best and Wu, 2020)

Methods

Results

Conclusion