A Non-motorized Treadmill Can Be A Valid Replacement For The Traditional Overground Six-minute Walk Test

The six-minute walk test (6MWT) is a commonly used clinical and research test to assess aerobic capacity. However, in many settings, the 30-m corridor required to conduct the test may not be available. Evaluation of the use of a non-motorized treadmill as an alternative method has not been well studied. PURPOSE: This study compared the distances walked during the traditional (TRAD) 6MWT on a flat indoor surface to a non-motorized treadmill (NMT) to validate the use of the NMT as an alternative testing method. METHODS: A total of 55 healthy adults (28 females) completed the TRAD 6MWT and NMT 6MWT during the same testing session (randomized order). The levels of agreement between the two methods were quantified using Lin’s concordance correlation coefficients. Additionally, a multiple linear regression was developed to predict TRAD 6MWT distance with covariates age, sex, and BMI from NMT distance walked. RESULTS: The average TRAD distance walked was 630 m and the average NMT distance walked was 607 m. The mean difference of 23 m between the two methods was nonsignificant. There was good agreement between methods (rc = 0.84) showing no differences. A multiple linear regression was developed and revealed that NMT distance significantly predicted TRAD distance when controlling for age, sex, height, and weight (Standardized Beta = 0.791, p < 0.001). Figure. Walk Test Method Comparison. rc = Lin’s concordance correlation coefficient, CI=Confidence Interval, r = Pearson’s correlation coefficient. CONCLUSIONS: The use of the NMT for 6MWT was deemed a valid and feasible replacement for the TRAD 6MWT based on the results of this study.Pilot Award from Athletic and Human Performance Research Center