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“Sit less, move more.” This message is being increasingly promoted in the world of health and fitness and in society at large and for good reason. The time we spend sitting is directly related to our health. In fact, too much sitting might even be harmful to people who exercise regularly. Sitting continuously for three hours has been shown to reduce the body’s ability to circulate blood flow to our legs, which may increase the likelihood of problems with our arteries. But we still don’t know how sitting affects other areas of the body where blood flows, such as the brain.

Maintaining brain blood flow is vital because the brain needs a constant supply of oxygen and nutrients to function and survive. Brain blood flow helps maintain our ability to perform cognitive tasks, such as decision-making and planning. It also helps prevent depression and other mood changes. Reduced blood flow to the brain is associated with the risk of developing diseases such as dementia later in life. This is why it is so important to find out if sitting—a behavior we spend so much time doing—has an influence on brain blood flow.

My colleagues and I recently published research in the Journal of Applied Physiology that has shown that sitting for long periods has a short-term negative effect on blood flow to the brain. In our study, we noticed a small reduction in blood flow in people who sat continuously for four hours. Interrupting the long stretches of sitting with short two-minute walking breaks every 30 minutes prevented this decline. However, when the participants took longer walking breaks every two hours, the physical activity was not able to prevent a reduction in brain blood flow.

More research is needed to see if walking breaks will prevent reduced blood flow to the brain over longer time periods. However, this study shows we should be getting up from our seat and moving around frequently. So, sit less and move more, more often!

Sophie Carter is a PhD candidate at the Research Institute for Sport and Exercise Sciences at Liverpool John Moores University, in Liverpool, England. Her research investigates the effect of sedentary behavior on cardiovascular health.