University of Minnesota researchers have good news for young adults who lead an active lifestyle: By staying active today, you may actually be preserving your memory and thinking skills in middle age.
The findings are most important for the young adults on the low and moderate end of fitness; the people with higher levels of fitness are already doing it right.
“Many studies show the benefits to the brain of good heart health,” said study author David R. Jacobs, Jr., Ph.D., at the University of Minnesota School of Public Health. “This is one more important study that should remind young adults of the brain health benefits of cardio fitness activities such as running, swimming, biking or cardio fitness classes.”
Jacobs emphasizes that for those on the lower end of fitness, cardio fitness activities themselves may even not be needed; just moving around in daily life and staying active can improve your future outlook.
So what does staying active have to do with memory retention?
While the thinking skills of humans are not well understood, it is known that the brain requires lots of oxygen to function properly. Subsequently, cardio fitness is a measure of how well the body transports oxygen to muscles, and how well muscles are able to absorb the oxygen during exercise.
For the study, 2,747 healthy people with an average age of 25 underwent treadmill tests the first year of the study and then again 20 years later. Cognitive tests taken 25 years after the start of the study measured verbal memory, psychomotor speed (the relationship between thinking skills and physical movement) and executive function.
During the treadmill test, participants walked or ran as the speed and incline increased until they could not continue. At the first test, participants lasted an average of 10 minutes on the treadmill. However, 20 years later that number decreased by an average of 2.9 minutes.
Participants of the study who lasted longer on the treadmill during the first test recalled more words correctly on the memory test 25 years later, even after adjusting for other factors such as smoking, diabetes and high cholesterol.
Furthermore, the people who had smaller decreases in their time completed on the treadmill test 20 years later were more likely to perform better on the executive function test than those who had bigger decreases. Specifically, they were better able to correctly state ink color (for example, for the word “yellow” written in green ink, the correct answer was “green”).
“These changes were significant, and while they may be modest, they were larger than the effect from one year of aging,” Jacobs said. “Other studies in older individuals have shown that these tests are among the strongest predictors of developing dementia in the future. One study showed that every additional word remembered on the memory test was associated with an 18-percent decrease in the risk of developing dementia after 10 years.”
“These findings are likely to help us earlier identify and consequently prevent or treat those at high risk of developing dementia,” Jacobs said. “The message is to engage in family, job, and community and in so doing move around, which will improve overall fitness.”
The study was published online in Neurology®, the medical journal of the American Academy of Neurology, and was supported by the National Heart, Lung, and Blood Institute and the National Institute on Aging.