Hip abductor neuromuscular capacity: A limiting factor in mediolateral balance control in older adults?
Mediolateral balance impairment is an important cause of falling in older adults. We aimed to investigate whether hip abductor muscular strength and/or position sense are limiting factors in mediolateral balance control.



Sixteen community-dwelling older adults performed three different mediolateral weight-shifting tasks, by tracking (1) a sinusoidally moving visual target, "visual-MELBA"; (2) a sinusoidally translating platform without explicit visual feedback, "mechanical-MELBA"; and (3) an unpredictable platform translation, "sudden-platform-translation." Balance performance was quantified for each task and correlated with hip abductor position sense, isometric strength, and peak hip abduction/adduction moments and moment rates.



Participants with better balance performance showed higher and faster hip abduction/adduction moment production during the tasks. Isometric hip abductor strength was significantly correlated with accuracy of tracking the visual target, while hip abductor position sense was associated with the bandwidth over which the mechanical target could be tracked and with a smaller delay between CoM movement and the sudden-platform movement.



Hip abductor muscles play an important role in mediolateral balance control. Accurate balance performance appears limited by lower hip abductor strength when explicit visual information on balance reduces the need for hip abductor proprioception, while proprioceptive acuity may limit balance performance when no explicit enhanced feedback is presented and required weight shifts have to be inferred from "normal" sensory information.
MOVE Research Institute Amsterdam, Department of Human Movement Sciences, VU University Amsterdam, Amsterdam, The Netherlands.
Mina
M
Arvin
MOVE Research Institute Amsterdam, Department of Human Movement Sciences, VU University Amsterdam, Amsterdam, The Netherlands. Electronic address: j.van.dieen@vu.nl.
Jaap H
JH
van Dieën
MOVE Research Institute Amsterdam, Department of Human Movement Sciences, VU University Amsterdam, Amsterdam, The Netherlands.
Gert S
GS
Faber
MOVE Research Institute Amsterdam, Department of Human Movement Sciences, VU University Amsterdam, Amsterdam, The Netherlands.
Mirjam
M
Pijnappels
MOVE Research Institute Amsterdam, Department of Human Movement Sciences, VU University Amsterdam, Amsterdam, The Netherlands; CORAL - Centre for Orthopaedic Research Alkmaar, Orthopaedic Outpatient Department, Medical Centre Alkmaar, Alkmaar, The Netherlands.
Marco J M
MJM
Hoozemans
Department of Rehabilitation Sciences, Faculty of Kinesiology and Rehabilitation Sciences, KU Leuven, Leuven, Belgium.
Sabine M P
SMP
Verschueren
D000368:Aged; D056228:Feedback, Sensory / Q000502:physiology; D005260:Female; D006621:Hip Joint / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology; D053580:Muscle Strength / Q000502:physiology; D018482:Muscle, Skeletal / Q000502:physiology*; D004856:Postural Balance / Q000502:physiology*; D011434:Proprioception / Q000502:physiology*; D016474:Weight-Bearing / Q000502:physiology
Accidental falls; Elderly; Hip abductor strength; Hip position sense; Postural balance; Sensory input