Tuberc Respir Dis.  2014 Jun;76(6):269-275.

Reference Equations for the Six-Minute Walk Distance in Healthy Korean Adults, Aged 22-59 Years

• Kim AL
• Kwon JC
• Park I
• Kim JN
• Kim JM
• Jeong BN
• Yu SK
• Lee BK
• Kim YJ

Abstract

BACKGROUND
The six-minute walk test has been widely used in people with chronic cardiopulmonary disorders as an outcome assessment with regards to therapeutic or prognostic determinants. This study was undertaken to determine the six-minute walk distance (6MWD) in a sample of healthy Koreans and to create a reference equation. We also compared the 6MWD of our cohort with previously published equations.
METHODS
Two hundred fifty-nine healthy subjects (95 males) aged 22-59 years performed two walking tests using a standardized protocol. 6MWD was defined as the greatest distance achieved from the two tests. The effect of anthropometrics on the 6MWD was also investigated.
RESULTS
The average 6MWD was 598.5+/-57.92 m, with significantly longer distances by males (628.9+/-59.51 m) than females (580.9+/-47.80 m) (p<0.001). Age, height, weight, and body mass index were significantly correlated with 6MWD in univariate analysis. Stepwise multiple regression showed height to be single independent predictor of 6MWD (r2=0.205, p<0.001). The reference equations derived in Caucasian and North African populations tend to overestimate the distance walked by Korean subjects, while Asian equations underestimate it.
CONCLUSION
The average 6MWD in these Korean populations was 600 m. The regression equation revealed that individual's height was the most significant predictor of distance, explaining 20.5% of the distance variance.

Keyword

Exercise Tolerance; Exercise Test; Physical Endurance; Reference Values; Healthy Volunteers

MeSH Terms

Adult*
Asian Continental Ancestry Group
Body Mass Index
Cohort Studies
Exercise Test
Exercise Tolerance
Female
Healthy Volunteers
Humans
Male
Physical Endurance
Reference Values
Walking

Figure

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  Figure 1 Relationships between six-minute walking distance (6MWD) and age (r=-0.219, p<0.001) (A), 6MWD and height (r=0.453, p<0.001) (B), and 6MWD and weight (r=0.355, p<0.001) (C). The linear regression line is superimposed, surrounded with the 95% confidence interval lines for the regression line.

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