Physical ftness and white matter microstructure in children with overweight or obesity: the ActiveBrains project

Abstract

Recent studies investigated the association of cardiorespiratory ftness with white matter microstructure in children, yet little work has explored to what extent other components of physical ftness (i.e., muscular or motor ftness) are associated with white matter microstructure. Indeed, this association has not been previously explored in children with overweight/obesity who present a diferent white matter development. Therefore, we aimed to examine associations between physical ftness components and white matter microstructure in children with overweight/obesity. In total, 104 (10.04 ± 1.15 years old; 43 girls) children were included in this cross-sectional study. Physical ftness was assessed using the ALPHA-ftness test battery. Fractional anisotropy (FA) and mean difusivity were derived from difusion tensor imaging (DTI). No association was found between physical ftness and global DTI metrics (all P> 0.082). Within individual tracts, all associations became non-signifcant when analyses were adjusted for multiple comparisons. Using the voxel-wise approach, we identifed a small cluster in the left lateral frontal lobe where children with greater upper-body muscular ftness showed higher FA (PFWE-corrected = 0.042). Although our results cannot conclude physical ftness is related to white matter microstructure in children with overweight/obesity; those fndings indicate that the association of muscular ftness with white matter microstructure might be more focal on frontal areas of the brain, as opposed to global diferences.