A study of overweight children in Spain found that children who had more physical activities early in the morning had healthier brain white matter microstructure. These children also tended to be happier compared to those who had fewer activities in the morning. The study was published in European Child & Adolescent Psychiatry.
Childhood is a period when the body undergoes rapid development. This development includes substantial changes to the structure of the brain. As the child grows, the structure of white matter of the brain develops as well. White matter is the tissue composed of nerve fibers that forms the communication network of the brain, allowing for the transmission of information and coordination of various brain functions.
Previous research has shown that lifestyle factors like physical activity, sleep, and diet can affect the structure of white matter during development. Researchers observed that children who are more physically active generally have better indicators of white matter structure.
Study author Irene Esteban‑Cornejo and her colleagues wanted to investigate the connection between early morning activities (such as active commuting to school, physical activity before school, having breakfast, and good sleep) and the microstructure of white matter in the brain. They specifically focused on overweight and obese children and wanted to explore whether white matter characteristics were associated with their mental health. While previous studies had linked early morning activity patterns to various health outcomes, it was unclear if these associations extended to brain structure.
The study included 110 overweight or obese children from Granada, Spain, who participated in the Active Brains Project conducted by the University of Granada. The children were between 8 and 11 years old, with 42 of them being girls. The data collection took place between 2014 and 2016.
The researchers assessed the children’s early morning activity patterns, breakfast habits, and sleep quality and duration. They also evaluated the children’s happiness, self-esteem, optimism, stress, depression, anxiety, and affect. Additionally, the children underwent magnetic resonance imaging (MRI) of their brains.
The researchers used diffusion tensor imaging, a technique that measures water molecule diffusion in brain tissues, to obtain information about the microstructural organization of white matter tracts. They analyzed various measures related to the integrity and organization of nerve fibers and used probabilistic fiber tractography to map white matter pathways in the brain.
The results indicated that individual morning behaviors were not associated with white matter microstructure. However, a higher overall level of physical activity in the morning was linked to better structural integrity of brain tissue and myelin (the substance that insulates nerve fibers).
Specifically, children who engaged in more morning activities had higher fractional anisotropy (indicating better brain tissue integrity) and lower radial diffusivity (indicating better myelin integrity) in the superior longitudinal fasciculus region of the brain. Moreover, children with better brain tissue and myelin integrity tended to be happier.
The study’s authors concluded that a combination of physically active early morning activities, particularly active commuting to school and physical activity before school, was associated with better white matter microstructure and increased happiness in overweight and obese children.
“Our findings suggest that a combination of physically active early morning activities, particularly active commuting to school and physical activity before school, is related to global and SLF [superior longitudinal fasciculus] tract-specific white matter indicators (functional anisotropy, radial diffusivity); and in turn, those white matter indicators are related to happiness. Therefore, these novel results suggest synergistic effects of physically active early morning patterns on white matter microstructure, coupled with better happiness in children with overweight or obesity,” they wrote in their study.
While this study contributes to our understanding of the relationship between brain structure and mental health in children, it has some limitations. The mental health and behavior assessments relied on self-reports, and the study only included children between 8 and 11 years old. Results might differ in other age groups, and the study’s design cannot establish cause-and-effect relationships.
The study, “Early morning physical activity is associated with healthier white matter microstructure and happier children: the ActiveBrains project”, was authored by Irene Esteban‑Cornejo, Inmaculada Lara‑Jimenez, Maria Rodriguez‑Ayllon, Juan Verdejo‑Roman, Andres Catena, Kirk I. Erickson, and Francisco B. Ortega.
