Source
Journals of Gerontology. Series A, Biological Sciences & Medical
Sciences.
52(2):M88-93, 1997 Mar.
Abstract
BACKGROUND: Falls may occur when an unexpected turn must be made
quickly, in order to avoid colliding with an
object in the gait path. Little is known about abilities,
particularly about abilities of old adults, to turn suddenly.
METHODS: Twenty young and 20 old (mean age 73.8) healthy and
physically active adults, while walking straight
ahead, were cued to make approximately a 90 degrees turn without
advance knowledge of where the turn was to be
made or whether it would be to the right or left. Subjects were given
available response times (ART), the times between
the cue to turn, and potential crossing of a specified forward limit
line, of 375, 450, 600, and 750 ms. The rate of
success (RS) in completing the turns as prescribed was determined.
Regression analyses were used to estimate the
additional ART that would be needed for other groups to achieve the
same RS as did the young male subject group.
RESULTS: For all ART, old subjects had a lower rate of success in
completing the turns as prescribed than the young.
At an ART of 375 ms, mean RS was 36% for the young and 6% for the
old. The regression analyses suggested that, for
RS from 30 to 95%, old adults needed 112 ms longer than young of
corresponding gender to succeed as well. Females
needed on the order of 50 ms longer ART than males of corresponding
age. CONCLUSIONS: There are significant
age and gender differences among healthy and physically active adults
in the available response times they need when
walking for successfully making sudden turns.