An equation to predict maximum oxygen consumption from the six-minute walk test in healthy young adults

Background: The six-minute walk test (SMWT) is an easy-to-use test that measures walking distance. Aim: To elaborate an equation to estimate the maximum oxygen consumption (VO2 max) using the results of the SMWT. Material and Methods: Forty men and 40 women aged 22.5 +/- 2 years, underwent a SMWT to measure the total walked distance and the recovery heart rate (RhR) Also, VO2 max was estimated from the maximal workload achieved in a cyclo- ergometer using the Storer test. A multivariate regression analysis resulted in a prediction equation that was validated with distributional assumptions of normality, independence and homoscedasticity. The limits of concordance of the predictive model were checked with the Bland-Altman diagram. Results: Body mass index (BMI), sex, RhR and total walked distance explained VO2 max variance by 3.4, 73.1, 17.9 and 32.8%, respectively. The prediction equation achieved was VO2 max (ml. min(-1)) = -3672.585 + (966.472 x Sex [1: female, 2: male]) + (-18.492 x RhR [beats. minute-1]) + (9.191 x Distance [m]) + (87.707 x BMI). The R-2 of the equation was 0.91 (p < 0.01). Conclusions: This equation predicts VO2 max in Chilean university students according to sex, BMI, cardiovascular response and performance in the SMWT.