Work

Human walking in the real world: Interactions between terrain type, gait parameters, and energy expenditure

Year: 2021

Type: article

Abstract: Humans often traverse real-world environments with a variety of surface irregularities and inconsistencies, which can disrupt steady gait and require additional effort. Such effects have, however, scarcely been demonstrated quantitatively, because few laboratory biomechanical measures apply outdoors. Walking can nevertheless be quantified by other means. In particular, the foot's trajectory in space can be reconstructed from foot-mounted inertial measurement units (IMUs), to yield measures of stride and associated variabilities. But it remains unknown whether such measures are related to metabolic energy expenditure. We therefore quantified the effect of five different outdoor terrains on foot motion (from IMUs) and net metabolic rate (from oxygen consumption) in healthy adults (N = 10; walking at 1.25 m/s). Energy expenditure increased significantly (P < 0.05) in the order Sidewalk, Dirt, Gravel, Grass, and Woodchips, with Woodchips about 27% costlier than Sidewalk. Terrain type also affected measures, particularly stride variability and virtual foot clearance (swing foot's lowest height above consecutive footfalls). In combination, such measures can also roughly predict metabolic cost (adjusted R2 = 0.52, partial least squares regression), and even discriminate between terrain types (10% reclassification error). Body-worn sensors can characterize how uneven terrain affects gait, gait variability, and metabolic cost in the real world.

Source: PLoS ONE

DOI: 10.1371/journal.pone.0228682

Authors: DB Kowalsky, JR Rebula, LV Ojeda, PG Adamczyk, AD Kuo

Institutions: University of Michigan, University of Wisconsin–Madison

Language: English

Topic: Balance, Gait, and Falls Prevention

Subfield: Physical Therapy, Sports Therapy and Rehabilitation

Field: Health Professions

Domain: Health Sciences

Open Access status: gold

Estimated APC paid: $1,749