Greater physical fitness is associated with more brain volume and greater white matter integrity, according to a study of 565 healthy, middle-aged subjects in the Coronary Artery Risk Development in Young Adults (CARDIA) study.
Researchers measured fitness by using symptom-limited maximal treadmill test duration (Maxdur), and followed up with brain MRIs 5 years later. They found for every 1-minute higher Maxdur, the odds ratio for having less whole brain volume was 0.85 and for having low white matter integrity was 0.80.
There were no significant associations observed between Maxdur and abnormal tissue volume or blood flow in white matter. Similar associations were found for associations with continuous brain MRI measures.
Citation: Zhu N, Jacobs DR Jr, Schreiner PJ, et al. Cardiorespiratory fitness and brain volume and white matter integrity: The CARDIA Study. Neurology. 2015;84(23):2347-2353. doi: 10.1212/WNL.0000000000001658.