title: Effects of narrow base gait on mediolateral balance control in young and older adults.
abstract: The aim of this study was to examine the effect of narrowing step width on mediolateral (ML) center of mass (COM) kinematics and margin of stability (MOS) in young and older adults. Fourteen young and 18 healthy older adults were asked to walk on a treadmill at preferred speed, stepping on projected lines at their predetermined preferred step width (PSW) and at a 50% narrowed step width (NSW). Linear trunk accelerations were recorded by an inertial sensor, attached at the level of the lumbar spine and foot placement was determined from force sensors in the treadmill. Mediolateral peak-to-peak COM displacement, COM velocity and MOS within strides were estimated. Mean ML-COM displacement and velocity, which were significantly higher in older compared to young adults, were significantly reduced in the NSW condition while the variability of ML-COM velocity was increased in the NSW condition. A significant interaction effect of step width and age was found for ML-COM velocity, showing larger decreases in older adults in the NSW condition. Walking with NSW reduced the ML-MOS significantly in both groups while it was smaller in the older group. Although reductions of ML-COM displacement and velocity may occur as direct mechanical effects of reduced step width, the larger variability of ML COM velocity in the older adults suggests active control of ML COM movements in response to the reduced base of support. Given the effects on MOS, narrowing step width might challenge ML-balance control and lead to less robust gait especially in older adults.
authors.affiliation: MOVE Research Institute Amsterdam, Department of Human Movement Sciences, Vrije Universiteit Amsterdam, The Netherlands.
authors.forename: Mina
authors.initials: M
authors.lastname: Arvin
authors.affiliation: MOVE Research Institute Amsterdam, Department of Human Movement Sciences, Vrije Universiteit Amsterdam, The Netherlands.
authors.forename: Masood
authors.initials: M
authors.lastname: Mazaheri
authors.affiliation: MOVE Research Institute Amsterdam, Department of Human Movement Sciences, Vrije Universiteit Amsterdam, The Netherlands; CORAL - Centre for Orthopaedic Research Alkmaar, Orthopaedic Outpatient Department, Medical Centre Alkmaar, The Netherlands.
authors.forename: Marco J M
authors.initials: MJM
authors.lastname: Hoozemans
authors.affiliation: MOVE Research Institute Amsterdam, Department of Human Movement Sciences, Vrije Universiteit Amsterdam, The Netherlands.
authors.forename: Mirjam
authors.initials: M
authors.lastname: Pijnappels
authors.affiliation: CORAL - Centre for Orthopaedic Research Alkmaar, Orthopaedic Outpatient Department, Medical Centre Alkmaar, The Netherlands.
authors.forename: Bart J
authors.initials: BJ
authors.lastname: Burger
authors.affiliation: Department of Rehabilitation Sciences, Faculty of Kinesiology and Rehabilitation Sciences, KU Leuven, Belgium.
authors.forename: Sabine M P
authors.initials: SMP
authors.lastname: Verschueren
authors.affiliation: MOVE Research Institute Amsterdam, Department of Human Movement Sciences, Vrije Universiteit Amsterdam, The Netherlands. Electronic address: j.van.dieen@vu.nl.
authors.forename: Jaap H
authors.initials: JH
authors.lastname: van Dieën
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology; D001696:Biomechanical Phenomena; D005080:Exercise Test; D005260:Female; D005528:Foot / Q000502:physiology; D005684:Gait / Q000502:physiology*; D006801:Humans; D008159:Lumbar Vertebrae / Q000502:physiology; D008297:Male; D004856:Postural Balance / Q000502:physiology*; D060726:Torso / Q000502:physiology; D016138:Walking / Q000502:physiology*; D055815:Young Adult
keywords: Active balance control; Ageing; Dynamic stability; Step width; Walking