Physical fitness improves brains in younger adults too

  • Large brain scan study found physical fitness was associated with better brain structure and better cognitive performance in younger adults.
  • A small study found greater aerobic fitness was linked to a larger entorhinal cortex (a brain region affected early in Alzheimer's disease).
  • A small study found endurance runners’ brains have greater functional connectivity than the brains of more sedentary age-matched individuals.

Data from a publicly available database of 1206 MRI brain scans from the Human Connectome Project has revealed that physical fitness is associated with better brain structure and brain functioning in young adults.

The volunteers (average age 29) had their physical fitness assessed using a "two-minute walking test", where each person is asked to walk as fast as possible for 2 minutes and the distance is then measured. Cognition was assessed using a series of cognitive tests to create a global cognition score.

Better performance on the 2-minute walking test was associated with better cognitive performance, and with structural integrity of the white matter in the brain. The association with better cognition was found in nearly all cognitive domains, but had particular benefits for fluid intelligence, cognitive flexibility, and processing speed.

Age, gender, BMI, and blood sugar levels, didn’t significantly affect these associations, but education did substantially weaken the association.

Aerobic fitness linked to bigger entorhinal cortex & better memory in young adults

A study involving 33 young adults (aged 18-35) found that those with greater aerobic fitness had a larger entorhinal cortex, and performed better on a recognition memory task.

The entorhinal cortex, which is part of the medio-temporal lobe (MTL) is affected early in Alzheimer’s disease.

Participants’ fitness was assessed using a treadmill test to measure aerobic capacity.

Runners’ brains may be more connected

Comparison of brain scans from 11 male collegiate distance runners and 11 age-matched controls has found that endurance runners’ brains have greater functional connectivity than the brains of more sedentary individuals (those who hadn’t engaged in any kind of organized athletic activity for at least a year).

https://www.eurekalert.org/pub_releases/2019-09/econ-tfa090919.phphttp://www.kurzweilai.net/importance-of-physical-activity-and-aerobic-exercise-for-healthy-brain-functionhttps://www.eurekalert.org/pub_releases/2016-12/uoa-rbm121416.php

Reference: 

Opel, N., Martin, S., Meinert, S. et al. White matter microstructure mediates the association between physical fitness and cognition in healthy, young adults. Sci Rep 9, 12885 (2019). https://doi.org/10.1038/s41598-019-49301-y

Whiteman, A. S., Young, D. E., Budson, A. E., Stern, C. E., & Schon, K. (2016). Entorhinal volume, aerobic fitness, and recognition memory in healthy young adults: A voxel-based morphometry study. NeuroImage, 126, 229–238. https://doi.org/10.1016/j.neuroimage.2015.11.049

Raichlen, D. A., Bharadwaj, P. K., Fitzhugh, M. C., Haws, K. A., Torre, G.-A., Trouard, T. P., & Alexander, G. E. (2016). Differences in Resting State Functional Connectivity between Young Adult Endurance Athletes and Healthy Controls. Frontiers in Human Neuroscience, 10. https://doi.org/10.3389/fnhum.2016.00610