How much walking does it take to keep your brain resilient against Alzheimer’s? Researchers have discovered the ideal amount of daily moderate exercise needed to protect the brain against tissue loss and cognitive decline in Alzheimer’s disease, according to a study published in the journal JAMA Neurology.
The study, conducted at Massachusetts General Hospital, saw brain health benefits in people who exercised modestly, but saw the highest results in those who walked 8,900 steps per day. That’s just under the 10,000 step goal many people aim for, and amounts to walking roughly 4.5 miles daily.
The study is among the first to prove the protective effects of exercise on the brain in people with high levels of beta-amyloid plaques but no symptoms of Alzheimer’s disease.
Beta-amyloid plaques, a hallmark of Alzheimer’s disease, are abnormal proteins in the brain that show up decades before the disease shows any symptoms. This is called the “preclinical” stage of Alzheimer’s disease.
Because there is no treatment for Alzheimer’s disease, researchers are eager to identify ways to intervene during this early stage of the disease to prevent symptoms from ever emerging.
“One of the most striking findings from our study was that greater physical activity not only appeared to have positive effects on slowing cognitive decline, but also on slowing the rate of brain tissue loss over time in normal people who had high levels of amyloid plaque in the brain,” says Jasmeer Chhatwal, MD, PhD of the MGH Department of Neurology, and corresponding author of the study.
This study suggests that higher levels of daily moderate exercise may reduce cortical thinning from beta-amyloid plaques and preserve gray matter in areas of the brain that are associated with memory loss and Alzheimer’s-related neurodegeneration. Walking is an activity most people can do, as it is low-impact and requires no special equipment.
For the study, researchers used pedometers to track the physical activity of 182 healthy older adults, including those with high levels of beta-amyloid and considered at high risk of Alzheimer’s.
According to co-author Reisa Sperling, MD, director of the Center for Alzheimer’s Research and Treatment, Brigham and Women’s Hospital and Massachusetts General Hospital and co-principal investigator of the Harvard Aging Brain Study, lifestyle interventions, like walking, that target cardiovascular health (heart, blood vessels, arteries, and veins) are especially important because they may offer additional protection against Alzheimer’s and delay progression of the disease.