From Passeig de Gràcia to the Sagrada Família: the 5,000 steps that can protect your brain

BarcelonaScience has long since proven that Staying physically active as you age significantly reduces the risk of developing dementia.It doesn't have to be a specific exercise: even a little walking helps strengthen the brain. Now, researchers in the United States have gone further and estimated that taking more than 5,000 steps a day can slow cognitive decline in people with preclinical Alzheimer's—that is, before the dysfunction and irreversible loss of neurons that appear once the first symptoms of the disease manifest have begun. Researchers at Mass General Brigham, a network of hospitals based in Boston, followed approximately 300 people for 14 years. These individuals had no symptoms of the disease but had an accumulation in their brains of two key proteins in the development of Alzheimer's. These proteins are called tau and beta-amyloid, and their accumulation in the brain is considered an unmistakable sign of the disease long before symptoms begin. Therefore, the authors conclude that all participants had preclinical Alzheimer's. According to the findings, published this Monday in the journal Nature MedicineExercising every day, such as walking, would slow the accumulation of the tabla protein and, therefore, the progression of the disease. This is one of the first studies to delve into the relationship between different levels of physical activity and these key proteins in Alzheimer's disease. Starting from the premise that a sedentary lifestyle is a risk factor for the onset of the disease, the study's authors have determined that even very moderate physical activity, such as walking between 3,000 and 5,000 steps a day, is associated with slower cognitive decline. However, according to the research findings, the benefits are greater and stabilize with physical activity that includes between 5,000 and 7,000 steps. For a simple example, this would be equivalent to walking the stretch between Passeig de Gràcia and the Sagrada Família, about 4 kilometers.

Physical activity and the brain

There is ample scientific evidence indicating that physical activity increases brain mass. It is common for older adults who begin walking for an hour a day to experience an increase in the volume of the hippocampus, the brain's memory center, slowing or reversing the age-related decline. It is also common for active middle-aged and older adults to perform better on memory and cognitive skills tests than people of the same age who rarely exercise. Furthermore, active individuals who develop dementia typically show the first symptoms years later than those who are less active. However, Charles Marshall, Professor of Clinical Neurology at Queen Mary University of London, argues that it is difficult to definitively say that physical activity is the cause of the slower progression of the disease observed by the study's authors. "We cannot say for sure that it is physical activity during this stage of adulthood that makes the difference, or whether those who are more active now have been so for decades and, therefore, the benefits accumulate," the expert explained in statements to Science Media CenterFurthermore, the expert acknowledges that these findings add to the abundant evidence suggesting that regular physical activity is good for the brain, in addition to all the other physical benefits it provides.