Automated stride assistance device reduces energy expenditure and improves gait parameters in healthy middle-aged women

Abstract

Background: Energy expenditure during walking is increased in patients with gait disorders. The physiological cost index (PCI), determined using MacGregor’s method, is one of the most useful ways for clinicians to assess energy expenditure during walking. Recently, several robotic gait assist devices have been developed to improve walking in patients with gait disorders, in terms of energy expenditure and gait parameters. However, conventional devices generally involve large equipment. In contrast, the Stride Management Assist device is lightweight and can be used outdoors. This device assists hip joint flexion and extension movements during walking, and may therefore decrease energy expenditure during walking in middle-aged women. Purpose: To investigate whether the Stride Management Assist device reduced energy expenditure and improved gait parameters during walking in healthy middle-aged women. Methods:Healthy middle-aged women (N= 9; mean age, 54.2± 3.9 y; height, 156.2± 6.3 cm; weight, 50.1± 4.3 kg) participated in this study. Subjects with cardiac disease, arrhythmia, or knee pain during walking were excluded. The Stride Management Assist device (Honda Motor Co., Ltd., Japan) was attached to the lumbar region and thigh. Subjects were assessed under two walking conditions at a comfortable speed (with or without robotic assistance). The assistance conditions were randomized and blinded. Subjects walked for 3minutes under each condition. Gait parameters (walking speed, step length, walk ratio), heart rate, and energy expenditure (defined by the PCI) were measured. The PCI was calculated as follows: (exercise heart rate− resting heart rate)×walking speed−1. TheWilcoxon signed-rank test was performed to compare gait parameters and the PCI between the conditions with and without robotic assistance. Results: Walking rate and step length differed significantly between the assist and no-assist conditions (p= 0.011 and p= 0.028, respectively). Walking speed was not significantly different between the two groups. The PCI tended to be lower with the robotic assistance condition than without that (p= 0.066). Conclusion(s):TheStrideManagementAssist devicewas useful for improving gait parameters and reducing energy expenditure during walking in healthy middle-aged women. Implications: This device may increase custom regular exercise among middle-aged women and increase their comfort during walking.