Bidirectional longitudinal associations of fatness with physical fitness in adolescents with Down syndrome. The UP&DOWN Longitudinal study

The aim of this study was to examine the bidirectional longitudinal associations of several markers of fatness and physical fitness in adolescents with Down syndrome.This study comprised a total of 111 adolescents (41 females), aged from 11 to 20 years with complete data at the baseline. We had a drop-out of10% from the baseline to the 2-year follow-up. The ALPHA health-related fitness test battery for youth was used.Our results show that all fatness variables at the baseline were associated with a 2-year change in cardiorespiratory fitness (β ranging from -0.32 to -0.38; all p .05), but not with muscular and motor fitness (p .05). However, no associations were found between physical fitness components as predictors and fatness indicators (p .05).Results suggest that reducing fatness during adolescence might represent a modifiable factor to improve cardiorespiratory fitness at the 2-year follow-up, but not vice versa since associations were not bidirectional.