Walking Speed Affects Gait Coordination and Variability Among Older Adults With and Without Mobility Limitations.

OBJECTIVE

To determine if poorer gait variability and gait coordination among mobility-limited older adults is related to their slower walking speed.

DESIGN

Cross-sectional analysis.

SETTING

University research laboratory.

PARTICIPANTS

Community-dwelling adults (N=69) 68 years or older with (Short Physical Performance Battery score ≤9; n=37) and without (n=32) mobility limitations.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The variability of step length, swing time percent, and step width. Gait coordination was assessed along with the Phase Coordination Index.

RESULTS

The usual pace gait speed of those without mobility limitations was faster (1.22±0.14m/s vs 0.71±0.14m/s; P<.001) and less variable in all gait characteristics (all P<.001), with the exception of step width (P=.185), than those with limitations. When those without limitations slowed their walking pace (0.71m/s±0.14), their gait coordination became poorer (P<.001), and the variability of all gait characteristics increased (all P<.001) except for step width, which decreased (P=.002). When those without mobility limitations walked at a slow pace, they had better gait coordination (P=.008) and less variable step length (P=.014) and swing time percent (P=.036). The variability of stride time (P=.260) and step width (P=.385) were not significantly different than that of their peers with limitations.

CONCLUSIONS

Increased variability in some gait characteristics of mobility-limited older adults appears to be related to their slower walking speed. Gait coordination and the variability of step length and swing time percent may reflect intrinsic differences in mobility-limited older adults that are independent of walking speed.