 This study found that females with overweight-slash-obesity had lower measures of integrity of the fimbriaphonics, a major limbic hippocampal white matter tract, than their lean peers, while this difference was not significant in males. Additionally, the study found a positive relationship between the number of days of aerobic physical activity completed in a week and integrity measures of the fimbriaphonics in females with overweight-slash-obesity. The results suggest that aerobic physical activity may play a role in reducing microstructural alterations in the fimbriaphonics in children with overweight-slash-obesity, but future work should examine causality and evaluate potential interventions to validate these effects. This article was authored by Ji Young Ma, Aaron C. Maglade, Rebecca S. Huber and others.