Psychologists discovered that a particular exercise aids episodic memory — 3 times a week for 4 months, with larger increases among people aged 55 to 68 years — after conducting a meta-analysis of 3,000 patients across 36 research (carefully vetted from more than 1,200 studies in total).
We all know that exercise is beneficial to our health, yet there are still a lot of unanswered concerns. How much physical activity do you get? Who stands to gain the most? And when did this happen in our lives? To address these issues, new study headed by University of Pittsburgh psychologists combines data from hundreds of trials, revealing that older persons may be able to avoid decreases in a certain kind of memory by exercising regularly.
“‘How much should I exercise?’ is a question that everyone has. What is the basic minimum that has to be done to observe progress?’ “Sarah Aghjayan, a PhD student in Clinical and Biological Health Psychology at the Kenneth P. Dietrich School of Arts and Sciences, is the primary author. “According to our research, you need exercise three times a week for at least four months to get the improvements in episodic memory.”
The kind of memory that deals with previous experiences is known as episodic memory. It’s also one of the first to deteriorate as you get older. “I typically prefer to speak about your first time behind the wheel of an automobile,” Aghjayan stated. “So you may recall where you were, how old you were, who was explaining things to you in the passenger seat, and how excited you were.”
Exercise that gets the heart beating has shown promise in improving brain health, and research in mice have demonstrated that it enhances memory — but results from human studies on the same topic have been inconsistent.
The researchers sifted through 1,279 papers in search of clarity in the muddled scientific literature, finally limiting it down to only 36 that satisfied precise criteria. The data was then transformed into a format that allowed the multiple research to be directly compared using specialist software and a large number of Excel files.
That hard effort paid off when they discovered that combining those 36 trials was enough to prove that exercise may help older persons’ memory. On February 17, the team, which included Aghjayan’s adviser Kirk Erickson from the Department of Psychology as well as other researchers from Pitt, Carnegie Mellon University, and the University of Iowa, published their findings in the journal Communications Medicine.
Previous studies that looked for a relationship between exercise and memory found none, but Aghjayan and her colleagues went above and above to give themselves the greatest chance of discovering one if one did exist. They focused their search on certain demographics and age groups, as well as a particular kind of rigorous experimental design. Another important factor was concentrating on episodic memory, which is aided by a brain region that has been shown to benefit from exercise.
“When we integrate and mix all of this data, we can look at over 3,000 people,” Aghjayan said. “Each research is significant in its own right: they all add to science in some manner.” Individual studies, on the other hand, may be unable to detect patterns that do exist due to a lack of resources to conduct a large-scale experiment. Individual studies couldn’t uncover a relationship between exercise and memory; it needed looking at the whole body of work to see the trend.
With a bigger sample size, the researchers were able to not only demonstrate a relationship between exercise and episodic memory, but also begin to address more precise questions about who benefits and how.
“We discovered that those aged 55 to 68 years old improved their memory more than people aged 69 to 85 years old, indicating that intervening sooner is beneficial,” Aghjayan added. The most beneficial benefits of exercise were identified in individuals who had not yet experienced any cognitive deterioration, as well as in trials where participants exercised many times per week.
There are still some unanswered questions. The team’s research couldn’t figure out how exercise intensity influences memory advantages, and there’s still a lot to learn about the mechanism at work. However, the public health ramifications are clear: Aghjayan believes that exercise is an accessible option for older persons to prevent memory loss, which benefits them, their caregivers, and the healthcare system.
“All you need is a nice pair of walking shoes and you can go out there and exercise your body,” says the author.
Kirk Erickson, Chaeryon Kang, Xueping Zhou, Chelsea Stillman, Shannon Donofry, Thomas W Kamarck, Anna L Marsland, and Scott H Fraundorf from the University of Pittsburgh, Themistokles Bournias from Carnegie Mellon University, and Michelle Voss from the University of Iowa are among the coauthors of the papers.