The Reliability and Validity of a 6-Minute Walk Test as a Measure of Physical Endurance in Older Adults

The purpose of this study was to assess the reliability and validity of a 6-min walk test as a measure of physical endurance in older adults. Seventy-seven subjects, ages 60-87. performed three separate 6-min walk tests and a treadmill test and completed questionnaire items assessing physical activity level and functional status. The 6-min walk had good test-retest reliability (.88 <R < .94). particularly when a practice trial preceded the test trial. Convergent validity of the 6-min walk was demonstrated by its moderate correlation (.71 < r < .82) with treadmill performance. Construct validity was assessed by determining the ability of the test to detect differences between different age and activity level groups. As expected, walking scores decreased significantly across decades and were significantly lower for low-active subjects compared to high-active subjects. There was a moderate relationship between 6-min walk scores and self-reported functional ability. It was concluded that the 6-min walk can be used to obtain reasonably reliable and valid measures of physical endurance in older adults and that it moderately reflects overall physical functional performance.