title: Age-related differences in the maintenance of frontal plane dynamic stability while stepping to targets.
abstract: Older adults may be vulnerable to frontal plane dynamic instability, which is of clinical significance. The purpose of the current investigation was to examine the age-related differences in frontal plane dynamic stability by quantifying the margin of stability and hip abductor moment generation of subjects performing a single crossover step and sidestep to targets that created three different step widths during forward locomotion. Nineteen young adults (9 males, age: 22.9±3.1 years, height: 174.3±10.2cm, mass: 71.7±13.0kg) and 18 older adults (9 males, age: 72.8±5.2 years, height: 174.9±8.6cm, mass: 78.0±16.3kg) participated. For each walking trial, subjects performed a single laterally-directed step to a target on a force plate. Subjects were instructed to "perform the lateral step and keep walking forward". The peak hip abductor moment of the stepping limb was 42% larger by older adults compared to younger adults (p<0.001). Older adults were also more stable than younger adults at all step targets (p<0.001). Older adults executed the lateral step with slower forward-directed and lateral-directed velocity despite similar step widths. Age-related differences in hip abduction moments may reflect greater muscular effort by older adults to reduce the likelihood of becoming unstable. The results of this investigation, in which subjects performed progressively larger lateral-directed steps, provide evidence that older adults may not be more laterally unstable than younger adults. However, age-related differences in this study could also reflect a compensatory strategy by older adults to ensure stability while performing this task.
authors: Department of Kinesiology and Nutrition, University of Illinois at Chicago, United States; Department of Physical Therapy, University of Alabama at Birmingham, United States. Electronic address: cphurt@uab.edu.
authors: Christopher P
authors: CP
authors: Hurt
authors: Department of Kinesiology and Nutrition, University of Illinois at Chicago, United States.
authors: Mark D
authors: MD
authors: Grabiner
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D001696:Biomechanical Phenomena / Q000502:physiology; D005260:Female; D005684:Gait / Q000502:physiology; D006621:Hip Joint / Q000502:physiology; D006801:Humans; D008124:Locomotion / Q000502:physiology*; D008297:Male; D009142:Musculoskeletal Physiological Phenomena; D004856:Postural Balance / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology; D014741:Video Recording; D016138:Walking / Q000502:physiology*
keywords: Biomechanics; Center of mass control; Gait; Hip moment; Lateral steps
references: J Am Geriatr Soc. 2002 Nov;50(11):1782-8
references: 12410895
references: PLoS One. 2011;6(7):e21815
references: 21779336
references: J Gerontol A Biol Sci Med Sci. 2000 May;55(5):M270-7
references: 10819317
references: Gait Posture. 2007 Feb;25(2):250-8
references: 16740390
references: Arch Phys Med Rehabil. 2008 Sep;89(9):1708-13
references: 18760155
references: J Biomech. 2010 Aug 10;43(11):2055-64
references: 20451911
references: J Biomech. 2005 Jan;38(1):1-8
references: 15519333
references: Neuropsychologia. 1998 Jan;36(1):37-43
references: 9533385
references: Med Care. 1992 Jun;30(6):473-83
references: 1593914
references: Gait Posture. 2014 Jan;39(1):135-40
references: 23850328
references: Arch Phys Med Rehabil. 2004 Apr;85(4):593-7
references: 15083435
references: J Appl Physiol (1985). 2000 May;88(5):1804-11
references: 10797145
references: J Biomech. 2008;41(7):1520-7
references: 18420214
references: Exp Brain Res. 2011 Oct;214(4):557-66
references: 21915670
references: J Biomech. 1993 Jun;26(6):633-44
references: 8514809
references: J Gerontol A Biol Sci Med Sci. 1996 Nov;51(6):M289-96
references: 8914501
references: Gait Posture. 2010 Mar;31(3):380-4
references: 20129786
references: Lancet. 1993 Jan 9;341(8837):72-5
references: 8093403
references: Clin Biomech (Bristol, Avon). 2009 Mar;24(3):267-73
references: 19136181
references: Gait Posture. 2010 Apr;31(4):461-4
references: 20185314
references: Gait Posture. 2008 Oct;28(3):466-71
references: 18400500
references: Clin Biomech (Bristol, Avon). 2005 Jul;20(6):607-16
references: 15890438