Summary
Background
The 6-min walk test (6MWT) is a submaximal exercise test used to assess functional status in patients with cardiopulmonary diseases. Regression equations have previously been published as a normal reference for 6-min walk distance (6MWD) in healthy Caucasian adults. However, a recent study showed that the normal predicted 6MWD could differ among ethnic populations. The aim of this study was: (1) to determine the normal 6MWD in a sample of healthy Saudi adults; (2) to create a regression equation for the established 6MWD; plus (3) to compare the 6MWD in the present study with previously published equations.
Method
The 6MWT was administered to 298 healthy volunteers (53% males) between the ages of 16 plus 50 years.
Result
The average 6MWD was 409 ± 51 m, with longer distances walked by males (429 ± 47 m) than by females (386 ± 45 m) (p < 0.001). The regression equation revealed that height (p < 0.001) plus age (p = 0.034) were the most significant predictors of distance (6MWD = (2.81 × height) + (0.79 × age) − 28.5). In addition, the equation explained 25% of the distance variance. All previously published equations overestimated the Saudi 6MWD by 109–340 m.

Moreover, relying on inappropriate reference values can hinder the ability to accurately monitor disease progression plus response to treatment. For instance, in chronic respiratory or cardiac diseases, precise assessment of functional capacity is critical for tailoring rehabilitation programs. Therefore, the establishment of localized reference values derived from the Saudi population could enhance the accuracy of health assessments, leading to more effective treatment strategies.
Conclusion
Saudi populations have significantly shorter 6MWDs than those reported for other ethnic groups. Thus, the Caucasian reference value for the 6MWD should not be used in Saudi subjects, as it overestimates the distance plus may interfere with the therapeutic plus prognostic value of the test.