Physical Activity and Body Composition Relate to Cardiorespiratory Fitness Independently in Young Adults with Down Syndrome

Abstract

BACKGROUND: Persons with Down syndrome (DS) typically possess low cardiorespiratory fitness (CRF), engage in low levels of physical activity (PA), and display elevated obesity levels, but the association between these variables is not clear in persons with DS. METHOD: We investigated the relationships among measures of CRF, PA, and body composition in 30 young adults with DS (age: 21.3 ± 5.5 years) using a cross-sectional study design. RESULTS: Male participants presented on average with a BMI of 32.9 ± 10.0 kg/m 2 , a percent body fat of 22.2 ± 13.0%, and a six-minute walk distance (6MWD) of 411.7 ± 66.3 m. Female participants presented on average with a BMI of 31.6 ± 13.5 kg/m 2 , a percent body fat of 26.7 ± 15.1%, and a six-minute walk distance (6MWD) of 360.4 ± 91.2 m. 6MWD shared a positive relationship with leisure time physical activity levels (r = 0.56, β = 1.488) and a negative relationship with body mass index (BMI; r = -0.49, β = -2.561). No relationship between body composition and PA was found. CONCLUSIONS: It seems that higher PA levels and lower BMI relate to better CRF in young adults with DS. Physical activity and body composition appear to be unrelated in persons with DS.