Physical Functioning, Physical Activity, and Variability in Gait Performance during the Six-Minute Walk Test.

Area of Science:

• Gerontology
• Biomechanics
• Physical Therapy

Background:

• The six-minute walk test (6MWT) is a common measure of functional capacity.
• Instrumenting the 6MWT with accelerometers can provide objective gait quality data.
• Physical activity and multi-directional stepping ability are crucial for fall risk reduction in aging adults.

Purpose of the Study:

• To investigate the relationship between gait quality during an instrumented 6MWT and physical functioning.
• To explore the association of 6MWT gait quality with free-living physical activity levels.
• To determine if instrumented 6MWT measures correlate with performance on the four square step test (FSST), a measure of multi-directional stepping.

Main Methods:

• Twenty-one older veterans (mean age 62.2 years) underwent an accelerometer-instrumented 6MWT.
• Participants also completed the FSST, a gait speed assessment, and health questionnaires.
• Free-living physical activity was monitored using an activity monitor worn at home.

Main Results:

• Increased stride time and stance time during the 6MWT were associated with lower self-reported physical functioning (p < 0.01).
• Greater stride time and stance time variability during the 6MWT correlated with longer FSST completion times (p < 0.05).
• Physical activity and sedentary time did not show significant relationships with 6MWT gait quality.

Conclusions:

• Instrumenting the 6MWT provides valuable insights into gait quality and functional limitations not detected by standard administration.
• Changes in gait parameters during the 6MWT, particularly variability, are linked to poorer multi-directional stepping ability and potentially higher fall risk.
• The FSST, especially at a 15-second threshold, effectively identifies individuals with poorer gait quality detected by the instrumented 6MWT.