Postural response in older adults with different levels of functional balance capacity.
OBJECTIVE
Aging is frequently accompanied by a deterioration in postural control, but it is not clear whether the primary contributor is increasing age or a progressive loss of functional balance capacity. The purpose of this study was to test the hypothesis that functional balance capacity contributes more than age to changes in postural response in the elderly.


METHODS
The study considered 3 groups of healthy young, and functionally-stable and functionally-unstable older adults (N = 16 each group). Postural responses, including behavioral response patterns, joint angular displacement, displacement of the center of mass and center of pressure, and ground reaction forces, were induced and examined by submitting standing subjects to unexpected backward displacements in the surface supporting them.


RESULTS
Functionally-stable older adults showed similar postural response patterns to those of young adults, whereas functionally-unstable older adults differed from young adults in the control of hip, trunk, shear force, and center of pressure trajectory during balance recovery.


CONCLUSIONS
These findings support the hypothesis that changes in postural control in the elderly correlate with their functional balance capacity and are not just a matter of age.
Lin
Sang-I
SI
Department of Physical Therapy, National Cheng Kung University, Tainan, Taiwan. lin31@mail.ncku.edu.tw
Woollacott
Marjorie H
MH
Jensen
Jody L
JL
D000058:Accidental Falls; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D001696:Biomechanical Phenomena; D006801:Humans; D004856:Postural Balance / Q000502:physiology*; D012678:Sensation Disorders / Q000503:physiopathology