From Lab to Life: How Exercise Helps Our Brains

We have two little dogs that need to be walked a lot, four times a day; one is elderly, the second is middle aged but has a common anal sac problem that is helped by frequent walks. The walks are for our doggies’ health – but, it turns out, they help mine as well. And those ab crunches I do in the gym –  well, my brain welcomes them as …a kind of trip to the car wash.

On May 1, Science Daily reports: “Scientists have uncovered a surprising link between simple body movement and brain health: every time you tighten your abdominal muscles—even slightly—your brain may gently sway inside your skull. This subtle motion, triggered by pressure changes in connected blood vessels, appears to help circulate cerebrospinal fluid around the brain, potentially flushing out harmful waste.” *

*  C. Spencer Garborg, Beatrice Ghitti, Qingguang Zhang, Joseph M. Ricotta, Noah Frank, Sara J. Mueller, Denver I. Greenawalt, Kevin L. Turner, Ravi T. Kedarasetti, Marceline Mostafa, Hyunseok Lee, Francesco Costanzo, Patrick J. Drew. Brain motion is driven by mechanical coupling with the abdomen. Nature Neuroscience, 2026; DOI: 10.1038/s41593-026-02279-z

How did Penn State scientists find this? “Using microCT scanning, which allows for high-resolution imaging of an organism’s internal structures, and other imaging techniques, researchers found that a network of veins serve as a mechanical connection between the abdominal cavity and the brain. When abdominal muscles tighten, they press on blood vessels connected to the spinal cord and brain. This pressure causes the brain to shift slightly within the skull. That gentle motion appears to help cerebrospinal fluid move across the brain, which may carry away waste that can interfere with normal brain function.”

Think of the brain as a sponge. How do you clean it? Squeeze it! Said one of the co-author researchers: “Keeping with the idea of the brain as a sponge, we also thought of it as a dirty sponge – how do you clean a dirty sponge?” Costanzo asked. “You run it under a tap and squeeze it out. In our simulations, we were able to get a sense of how the brain moving from an abdominal contraction can help induce fluid flow over the brain to help clear waste products.”

So, let’s help our brains – get up out of our easy chairs and …move it. It does seem that exercise helps both move oxygen and energy to our organs (see my piece on sore knees) and also remove waste products. Makes sense.