Validity of the 16-metre PACER and six-minute walk test in adults with Down syndrome.

Abstract

The purpose was to establish criterion-related validity of the 16-metre PACER and six-minute walk distance (6MWD) tests to VO2 peak as well as predictors of VO2 peak in adults with Down syndrome (DS). Adults with DS (24 males and 19 females) aged 18-50 years performed the three aerobic tests on non-consecutive days during a one-week period. To assess validity, peak oxygen uptake was measured directly on a motorized treadmill. Pearson-product moment correlations were performed. Predictors of VO2 peak were assessed with a stepwise multiple regression analysis. Agreement between PACER and VO2 peak was assessed by Bland-Altman plot. Linear regression revealed that the PACER (R(2 )=( )0.86) and the 6MWD (R(2 )=( )0.75) were significantly related to VO2 peak (p < 0.05). Both the 16-metre PACER and the 6MWD significantly correlated with VO2 peak for adults with DS. The relationship was stronger for the 16-metre shuttle run test (r = 0.87) than the 6MWD (r = 0.78). The correlation between VO2 peak and both field tests, controlling for age, gender and BMI, remained significant (r > 0.7; p < 0.05). PACER, 6MWD and BMI are significant predictors of VO2 peak (p < 0.05). The 16-metre PACER and 6MWD are valid field tests for predicting aerobic capacity in adults with DS. Implications for Rehabilitation The 16-metre PACER and 6MWD tests are safe and feasible for use in adults with DS. Both tests are valid indicators of cardio-respiratory fitness as assessed by moderate-to-strong coefficients of determination and correlation coefficients. Both field tests along with BMI are predictors of aerobic capacity.