New research from Penn State University suggests that engaging your abdominal muscles may have an unexpected benefit: helping regulate blood flow in the brain.
Most people don’t look forward to doing sit-ups. But new research from Penn State University suggests that engaging your abdominal muscles may have an unexpected benefit: helping regulate blood flow in the brain.
Researchers discovered that when the body moves and the abdominal muscles contract, pressure changes in blood vessels connected to the brain through the spinal column. Those pressure changes can trigger extremely rapid constrictions in major veins within the brain, temporarily increasing blood flow.
The findings, published in the Proceedings of the National Academy of Sciences, provide new insight into how movement throughout the body can influence what happens inside the brain.
The study was conducted in mice, so more research is needed to determine whether the same process occurs in humans. However, the researchers noted that the underlying physiological structures are similar between mice and humans.
"Our findings show that mechanical signals generated by the body can have immediate consequences for the circulation inside the skull," said Qingguang Zhang, the study's first author and a former assistant research professor at Penn State.
The brain may be protected inside the skull, but it isn't mechanically isolated from the rest of the body.
Everyday activities such as walking, running, breathing and coughing can change pressure throughout the body. The Penn State researchers found that abdominal muscle contractions can also influence blood flow within the brain.
The discovery challenges the traditional view that blood flow in the brain is regulated primarily by arteries and capillaries.
Arteries and capillaries contain muscle that allows them to expand and contract, helping direct blood to areas of the brain that need more oxygen and nutrients. Veins, on the other hand, have generally been viewed as more passive structures that simply carry blood away from the brain.
They observed rapid constrictions in the superior sagittal sinus, a large vein running along the top of the brain, as well as smaller veins that connect to it. These changes occurred within approximately one-tenth of a second after abdominal muscles were activated.
"Veins are not simply passive pipes," Zhang said. "What happens to blood as it leaves the brain can be just as dynamic and physiologically important."
The findings don't mean that doing sit-ups will necessarily improve your brain health. The study did not test sit-ups or measure long-term health benefits in humans.
Instead, it reveals another way physical movement may affect the brain. Activities that engage the core, including exercise, walking and even coughing, can create mechanical changes in the body that appear to influence circulation inside the skull. This could help researchers better understand the complex relationship between physical activity and brain function.
The discovery may also help explain why some people experience changes in headaches or migraines during physical activity. The veins involved in the study are located in the dura, the protective membrane surrounding the brain. The dura contains pain receptors that are believed to play a role in headaches and migraines.
The researchers say understanding these mechanisms could eventually help scientists better understand conditions involving abnormal brain blood flow or movement-related headaches.
For now, the study offers an interesting reminder that exercise affects far more than our muscles and cardiovascular system. Something as simple as contracting your abdominal muscles can create rapid changes throughout the body—including changes that reach all the way to the brain.
So while this research isn't necessarily a reason to start doing sit-ups, it adds another piece to the growing picture of how closely connected movement, circulation and brain health really are.
Click here to read more in the Proceedings of the National Academy of Sciences.
