Exercise in older adults can improve health in many ways, and a new study has shown how even the brain can benefit. When most people think of exercise, they think it needs to be a long, strenuous workout to gain any real benefits, but this new research shows how even a single exercise session can bring results.
The study from the University of Iowa has found even something as small as a single bout of exercise improves working memory and cognitive functions in older adults. Using experiments that included physical activity, brain scans, and working memory tests, the researchers found surprising results. Participants experienced the same cognitive benefits and improved memory from a single exercise session as they did from longer, regular exercise.
There have been many previous studies that show how exercise can boost mental health, but until now, there has been limited information on how a single bout of physical activity may affect cognition and working memory.
“One implication of this study is you could think of the benefits day by day,” says Michelle Voss, assistant professor in the Department of Psychological and Brain Sciences and the study’s corresponding author. “In terms of behavioral change and cognitive benefits from physical activity, you can say, ‘I’m just going to be active today. I’ll get a benefit.’ So, you don’t need to think of it like you’re going to train for a marathon to get some sort of optimal peak of performance. You just could work at it day by day to gain those benefits.”
Brain Scan and Memory Test
For the study, 34 adults between 60 and 80 years of age who were healthy, but not physically active were enrolled. Each participant was required to ride a stationary bike on two separate occasions. The first time would be light exercise, while the second would be more strenuous resistance when pedaling for 20 minutes. Each participant underwent a brain scan and completed a memory test both before and after each exercise session.
The brain scan showed that there were bursts of brain activity in regions known to be involved in the collection and sharing of memories. For the working-memory tests, each participant looked at eight young faces on a computer screen, flashcard style, and then had to decide if a face seen previously matched the one they were currently viewing.
It was found that after a single exercise session, some individuals increased connectivity between the medial temporal, and the parietal cortex and prefrontal cortex, two regions that are involved in cognition and memory. These same participants also showed better performance on the memory tests, whereas other participants showed little to no gain.
“The benefits can be there a lot more quickly than people think,” Voss says. “The hope is that a lot of people will then keep it up because those benefits to the brain are temporary. Understanding exactly how long the benefits last after a single session, and why some benefit more than others, are exciting directions for future research.”
Most participants in the light to moderate intensity groups showed mental benefits at the beginning and end of the three-month exercise period. This meant that the brain gains were no more significant than the improvements from when participants had only exercised a single time.
“The result that a single session of aerobic exercise mimics the effects of 12 weeks of training on performance has important implications both practically and theoretically,” the authors write.
Further research is needed to address the limitations of the study. Voss has now expanded her participant pool in a current five-year study to confirm the initial findings and to learn more about exercise and the brain.