The World Health Organization promotes physical exercise and a healthy lifestyle as means to improve youth development. However, relationships between physical lifestyle and human brain development are not fully understood. Here, we asked whether a human brain–physical latent mode of covariation underpins the relationship between physical activity, fitness, and physical health measures with multimodal neuroimaging markers. In 50 12-year old school pupils (26 females), we acquired multimodal whole-brain MRI, characterizing brain structure, microstructure, function, myelin content, and blood perfusion. We also acquired physical variables measuring objective fitness levels, 7 d physical activity, body mass index, heart rate, and blood pressure. Using canonical correlation analysis, we unravel a latent mode of brain–physical covariation, independent of demographics, school, or socioeconomic status. We show that MRI metrics with greater involvement in this mode also showed spatially extended patterns across the brain. Specifically, global patterns of greater gray matter perfusion, volume, cortical surface area, greater white matter extra-neurite density, and resting state networks activity covaried positively with measures reflecting a physically active phenotype (high fit, low sedentary individuals). Showing that a physically active lifestyle is linked with systems-level brain MRI metrics, these results suggest widespread associations relating to several biological processes. These results support the notion of close brain-body relationships and underline the importance of investigating modifiable lifestyle factors not only for physical health but also for brain health early in adolescence.

SIGNIFICANCE STATEMENT An active lifestyle is key for healthy development. In this work, we answer the following question: How do brain neuroimaging markers relate with young adolescents' level of physical activity, fitness, and physical health? Combining advanced whole-brain multimodal MRI metrics with computational approaches, we show a robust relationship between physically active lifestyles and spatially extended, multimodal brain imaging-derived phenotypes. Suggesting a wider effect on brain neuroimaging metrics than previously thought, this work underlies the importance of studying physical lifestyle, as well as other brain–body relationships in an effort to foster brain health at this crucial stage in development.

世界卫生组织提倡体育锻炼和健康的生活方式，以此作为改善青少年发展的手段。然而，身体生活方式与人类大脑发育之间的关系尚不完全清楚。在这里，我们询问人脑-身体潜在的共变模式是否支持身体活动、健身和身体健康指标与多模式神经影像标记之间的关系。我们对 50 名 12 岁小学生（26 名女性）进行了多模态全脑 MRI 扫描，表征了大脑结构、微观结构、功能、髓磷脂含量和血液灌注。我们还获得了测量客观健康水平、7 天体力活动、体重指数、心率和血压的身体变量。使用典型相关分析，我们揭示了大脑-身体协变的潜在模式，与人口统计、学校或社会经济地位无关。我们表明，更多地参与这种模式的 MRI 指标也显示出整个大脑的空间扩展模式。具体来说，更大的灰质灌注、体积、皮质表面积、更大的白质神经突外密度和静息状态网络活动的整体模式与反映身体活跃表型（高适应度、低久坐个体）的测量呈正相关。这些结果表明，身体活跃的生活方式与系统级脑部 MRI 指标相关，表明与多种生物过程相关的广泛关联。这些结果支持了大脑与身体密切关系的概念，并强调了研究可改变的生活方式因素的重要性，不仅对身体健康而且对青春期早期的大脑健康也很重要。

意义陈述积极的生活方式是健康发展的关键。在这项工作中，我们回答以下问题：大脑神经影像标记物与青少年的体力活动、健身和身体健康水平有何关系？将先进的全脑多模态 MRI 指标与计算方法相结合，我们展示了身体活跃的生活方式与空间扩展的多模态脑成像衍生表型之间的牢固关系。这项工作对大脑神经影像指标的影响比之前想象的更广泛，它强调了研究身体生活方式以及其他大脑与身体关系的重要性，以努力在这个发育的关键阶段促进大脑健康。