Objective. The purpose was to identify age-related changes in the abil
ity to step sideways during gait. Design. Sixteen young women (mean ag
e 27) and 16 older women (mean age 70) were tested. Background. The ab
ility to safely incorporate changes of direction into our walking patt
ern at short notice is a requirement for full mobility. Side-stepping
in particular is frequently used to avoid obstacles. Methods. The task
was to walk repeatedly down the center of a walkway divided into thre
e parallel lanes. A suddenly-appearing visual cue instructed the subje
ct to move to either the right or left lane or to remain in the center
lane. The aim was to make the shift accurately but as quickly as poss
ible, without halting forward progression. Results. In only 26% of the
trials by the older women was the shift accomplished by taking just o
ne extra step, compared with 58% of the trials by the young women. For
one of the two shift directions there was no significant difference b
etween the groups in either speed changes or foot placement accuracy.
For the other direction, however, the young women incorporated the shi
ft with no significant change in average speed; the older women's spee
d decreased by 3.3%, The older women also made more errors in foot pla
cement in the steps following the side-step (a 22% error rate compared
to a 3% error rate). Conclusions. Older women were less able to quick
ly and accurately incorporate a sideways shift in the plane of progres
sion into their comfortable walking pattern.