The six-minute walk test cannot predict peak cardiopulmonary fitness in ambulatory adolescents and young adults with cerebral palsy.

Abstract

To determine whether the 6-minute walk test (6MWT) is predictive of peak oxygen consumption (Vo(2)peak) and whether the 6MWT is a clinically applicable alternative to cardiopulmonary exercise testing (CPET) in ambulatory adolescents and young adults with cerebral palsy (CP). Cross-sectional. University hospital and rehabilitation centers. Adolescents and young adults with CP (N=41) classified in Gross Motor Function Classification System (GMFCS) level I or II. Not applicable. The covered distance during 6 minutes was measured with a 6MWT. The Vo(2)peak was obtained with CPET on a cycle ergometer. Univariate linear regression analysis was used to study the relationship between the outcomes of both tests. A multiple linear regression analysis was performed to determine whether Vo(2)peak could be predicted by the 6MWT, sex, body mass, and GMFCS level. A significant relationship (P<.01) was found between the outcomes of the 6MWT and CPET, with an explained variance of 21%. The multiple linear regression analysis showed an explained variance of 58% and a standard error of estimate (SEE) corresponding to 18% of the mean Vo(2)peak. The 6MWT is poorly related to Vo(2)peak in ambulatory adolescents and young adults with CP. Because of a high SEE, the multiple regression model did not allow for prediction of Vo(2)peak from the 6MWT in ambulatory adolescents and young adults with CP.