Older people can prevent memory decline by sticking to regular exercise
We all know exercise is good for us, but that still leaves a lot of questions. How much exercise? Who benefits the most? And when in our lives? New research by psychologists at the University of Pittsburgh pools data from dozens of studies to answer these questions, showing that older adults may be able to prevent the decline of a certain type of memory by getting older. by sticking to regular exercise.
Everyone always asks, ‘How much should I exercise? What is the bare minimum to see an improvement? » . From our study, it appears that exercising about three times a week for at least four months is what you need to reap the benefits of episodic memory.”
Sarah Aghjayan, lead author, doctoral student in clinical psychology and health biology at the Kenneth P. Dietrich School of Arts and Sciences
Episodic memory is one that deals with events that happened to you in the past. It is also one of the first to decline with age. “I usually like to talk about the first time you got behind the wheel of a car,” Aghjayan said. “So you might remember where you were, how old you were, who was in the passenger seat explaining things to you, that feeling of excitement.”
Heart-pounding exercise has shown promise for improving brain health, and experiments in mice show it improves memory -; but studies investigating the same link in humans are mixed.
Seeking to clear the muddy waters of the scientific literature, the team looked at 1,279 studies, ultimately whittling them down to just 36 that met specific criteria. Then they used specialized software and a large number of Excel spreadsheets to transform the data information into a form where the different studies could be directly compared.
This work paid off when they found that pooling these 36 studies together was enough to show that for older people, exercise can indeed benefit their memory. The team, including Aghjayan’s adviser Kirk Erickson in the Department of Psychology and other researchers from Pitt, Carnegie Mellon University and the University of Iowa, published their findings in the journal Communication Medicine February 17.
Past analyzes looking at links between exercise and memory have found none, but Aghjayan and his team took several additional steps to give them the best chance of finding a link if one existed. They limited their research to particular groups and age groups as well as a specific type of rigorous experimental design. Another key was to focus specifically on episodic memory, which is supported by a part of the brain known to benefit from exercise.
“When we combine and merge all of this data, it allows us to look at nearly 3,000 participants,” Aghjayan said. “Each individual study is very important: they all contribute to science in a significant way.” However, individual studies may not find models that actually exist due to a lack of resources to conduct a large enough experiment. The studies individually could not find a link between exercise and memory -; all of the research had to be looked at to develop the model.
With this much larger group of participants, the team was able to show a link between exercise and episodic memory, but also could begin to answer more specific questions about who benefits and how.
“We found that there were greater memory improvements in people aged 55 to 68 compared to those aged 69 to 85 – so it’s better to intervene earlier,” he said. Aghjayan. The team also found the greatest effects of exercise in those who had not yet experienced cognitive decline and in studies where participants exercised regularly several times a week.
There are still questions to be answered. The team’s analysis couldn’t answer how exercise intensity affects memory benefits, and there’s a lot to learn about the mechanism behind this link. But the public health implications are clear: Exercise is an accessible way for older people to stave off memory decline, benefiting themselves, their caregivers and the healthcare system, Aghjayan said. .
“You just need a good pair of walking shoes, and you can get out there and move your body.”
Aghjayan, SL, et al. (2022) Aerobic Exercise Improves Episodic Memory in Late Adulthood: A Systematic Review and Meta-Analysis. Communication Medicine. doi.org/10.1038/s43856-022-00079-7.