She is getting better. A new study has found that exercise boosts levels of a protein known to strengthen communication between brain cells across synapses, which may be a key factor in preventing dementia.
The protective effect was found even in active older adults whose brains showed signs of plaques, tangles, and other hallmarks of Alzheimer’s and other cognitive diseases.
Study author Kaitlin Casaletto, assistant professor of neuroscience at the Center for Memory and Aging at the University of California San Francisco, said in an email.
“All of our thinking and memory happens as a result of these intertwined connections,” she added.
Casalito explained that previous studies have shown that physical activity can reduce the risk of dementia by 30% to 80%, “but we don’t understand how this happens at a biological level in humans.”
“We describe, for the first time in humans, that synaptic functioning may be a pathway through which physical activity enhances brain health,” she said, adding that the study could only show an association, not necessarily cause and effect.
However, Casalito added, “I believe these findings begin to support the dynamic nature of the brain in response to our activities, and the ability of the aging brain to elicit healthy responses to activity even at older ages.”
Protein regulation is key
A well-functioning brain keeps electrical signals transmitted smoothly through synapses from neurons to neurons and to other cells in the body. To do this, the brain constantly needs to replace the worn out proteins in those synapses, while also making sure that they are properly balanced and organized.
“There are many proteins present in the synapse that help facilitate different aspects of cell-to-cell communication. These proteins must be in balance with each other for the synapse to function optimally,” Casalito wrote.
This is all part of how the brain reshapes its neural circuits, keeping them healthy.
Studies in mice have long demonstrated the protective effect of exercise on the brain once an autopsy has taken place, but proving this link in humans has been difficult.
As part of this project, the late-life physical activity of elderly participants was also tracked. The results showed that people who moved more had more protective proteins.
“The more physical activity, the higher the levels of synaptic protein in brain tissue. This suggests that every movement matters when it comes to brain health,” Casalito said.
“We recommend aiming for 150 minutes per week of physical activity,” she added by email. “Previous studies have shown that even walking is associated with a reduced risk of cognitive decline!”
She added that it appears to work independently of whether a person already has signs of Alzheimer’s disease and other types of dementia.
“Many previous studies consistently show … higher levels of these same synaptic proteins in brain tissue are associated with better cognitive performance, independent of plaques and tangles,” she wrote.
“This data reinforces the importance of integrating regular physical activity into our daily lives — no matter how young or old we are,” said Heather Snyder, vice president of medical and scientific relations for the Alzheimer’s Association, which partially funded the study.
Snyder, who was not involved in the study, added.
How do you move
“Start with just 5-10 minutes of walking a day for the first few days as you figure out the best time and place to walk,” Santas said. “Once you identify the logistics, start adding a few more minutes to each walk. Ideally, you want to get in up to 20 to 30 minutes a day.”
Santas recommends making it a habit as important as adding movement to your life.
“Take steps to make it sustainable so that it becomes a part of your lifestyle that you enjoy and are proud of rather than looking at it negatively, like a chore,” Santas said.
“For nearly eight years now, I’ve been doing 50 bodyweight squats or sitting for two minutes on a wall while brushing my teeth,” Santas told CNN.
Adding movement to everyday tasks can add a quick boost. Let’s say you get up and move three times an hour during your workday.
“That’s 24 minutes of exercise a day,” Santas said. “Add another 10 minutes of walking or climbing stairs before or after work, and it’ll be 34 minutes a day, or 170 minutes per five-day workweek.”
“This far exceeds the weekly limit of 150 minutes, or two and a half hours, recommended by the World Health Organization – without ever setting foot in the gym.”