• Posted March 25, 2026

Want To Protect Your Brain? Science Says Exercise

Lunges and squats may do more for the brain than previously thought, including helping protect it from damage tied to aging and dementia, a new study suggests.

In research published this month in the journal Cell, scientists found that physical activity may help repair the blood-brain barrier, a layer of cells that protects the brain from harmful toxins and pathogens.

This barrier naturally weakens as people age, which can lead to inflammation and increase risk for conditions like dementia.

The new study, conducted in mice, found that exercise triggers the release of a protein made in the liver. That protein travels through the bloodstream and helps strengthen the brain’s protective barrier.

While results of animal studies often differ in people, this study is promising, observers said.

“These results provide compelling evidence in animal models that exercise-related signals from the liver can improve brain function by acting on the blood-brain barrier,” Michelle Voss, director of the University of Iowa’s Health, Brain and Cognition Lab, told The Washington Post. She reviewed the findings but was not involved in the study.

Researchers focused on a protein called GPLD1, which is released during and after exercise.

Scientists had previously found that older mice performed better on memory tests after receiving blood from mice that had been active.

In this new study, they took their inquiry a step farther.

They genetically upped GPLD1 levels in older mice that did not exercise. Even without activity, those mice showed better memory and learning and had signs of healthier brain cells.

Surprisingly, the protein itself did not enter the brain.

Instead, it likely worked outside the brain by improving the protective blood-brain barrier.

The team found that aging brains had higher levels of a harmful protein called TNAP, which can make the protective barrier more porous.

Older mice that exercised had lower levels of TNAP. When researchers increased GPLD1 in inactive mice, it helped remove excess TNAP. This made the barrier stronger and less "leaky."

As a result, brain tissue was better protected, and the mice performed better on thinking tests.

Scientists say the findings may help explain why exercise supports brain health.

They also hinted at a future initiative aimed at creating treatments that copy some of the effects that exercise provides, especially for people who cannot exercise.

But experts warned that "many promising exercise-related pathways in mice turn out to be more complicated in humans," David Raichlen, an evolutionary biologist at the University of Southern California who also wasn't involved in the research, told The Post.

Researchers hope to begin human studies soon. But they stress that no pill or procedure can fully replace exercise.

“If you can, exercise,” said senior author Saul Villeda, a professor of biomedical sciences at the University of California, San Francisco. “It’ll always be one of the best things you can do” for your health.

More information

Harvard Health has more on the best exercises that support brain health.

SOURCE: The Washington Post, March 24, 2026