- Physical activity of any kind appears to increase a person’s cognitive processing speed, according to a new study.
- While it is generally accepted that moderate-to-vigorous exercise benefits brain health, this study finds that any physical activity at all carries with it some cognitive benefit.
- The study leveraged mobile phones to allow researchers to survey study participants regarding their activity levels nearly in realtime, and to test their cognitive processing speed multiple times during the day.
- The positive effect of being active may have to do with a heightened sense of alertness that comes with physical movement.
Everyday physical activity offers a boost in short-term brain processing speed, according to the findings of a new study from researchers at Penn State College of Medicine.
The study found that common day-to-day activities, regardless of intensity, can provide a short-term improvement in mental reaction time similar to reducing one’s cognitive age by four years.
Previous research has established the value of moderate-to-vigorous physical activity for maintaining cognitive health — and for good health in general.
This study — published in Annals of Behavioral Medicine — uniquely investigates the potential benefit of activities in which people commonly engage during the course of their day, both at work and at home.
One of the study’s strong points was that it collected participant data almost in real time. For 7 days, participants were surveyed five times a day in an app on their mobile phones regarding their physical activity since their last questioning. At each survey, they also took part in two sets of brain games within the app.
The first game was a symbol-search task in which they were asked to tap a symbol at the bottom of their screen that matched the one displayed at the top. After twelve rounds, their average response time was recorded in the app.
Scores for the symbol-search game, which tested brain processing speed, improved after periods of physical activity.
In the second game, they were asked to recall the location of three dots in a five-by-five grid a few moments after they had been temporarily replaced by a grid of “e”s and “f”s. They played four rounds of the game, with the app scoring their accuracy and calculating their average score.
The researchers saw no improvement in scores for this game that tested working memory after physical activity, although participants did respond more quickly, however inaccurately.
Corresponding author Jonathan G. Hakun, PhD, an assistant professor of neurology, psychology, and public health sciences at Penn State, explained for Medical News Today how technology made this sort of real-world study possible.
“It’s a very different approach in that the real novelty is the ability to sample cognition out in everyday life with a smart application,” he said.
Hakun said that, as a person ages, their cognitive processing speed may slow by as much as 15 milliseconds (ms) a year.
The increase in speed exhibited by participants in the study who engaged in physical activity was about 60 ms, the equivalent of gaining back about 4 years’ worth of cognitive processing speed.
At the start of the study, participants were taught how to categorize the activities they were to report to their app.
Light activity included walking to meetings, household chores, walking their dogs, cleaning, and other activities requiring minimal effort.
Brisk walking, nonstrenuous biking, and jogging made up the bulk of moderate-intensity activities that the participants engaged in. Running, fast cycling, and difficult hiking were some examples of vigorous activity.
Some jobs involve plenty of physical activity during work hours. Hakun recalled “a friend who works for UPS, and whenever we did those Fitbit competitions years ago he would get 25,000 steps without even thinking about it.”
Vernon Williams, MD, a sports neurologist and founding director of the Center for Sports Neurology and Pain Medicine at Cedars-Sinai Kerlan-Jobe Institute in Los Angeles, who was not involved in the study, told MNT that the research “is interesting in that it suggests that there is at least a short-term benefit from everyday activity, not just moderate or high intensity ‘exercise.’”
“It underscores our belief that movement — any movement — is generally a good thing,” added Williams.
“We’ve known that multiple previously published work, and the overall impression has been, that exercise has a positive effect on cognitive function, including processing speed,” Williams explained for MNT.
As to why that may be, he noted that:
“With higher-intensity exercise, and longer duration exercise, there are benefits thought to be related to the release of certain chemicals, neurotransmitters, and factors in the brain that are good for cognitive health. There’s also the concept that physical exercise and activity are associated with improved cardiovascular function, improved blood flow, reduced blood pressure, etc. — all associated with improved cognitive function.”
Insofar as the short-term speed gains seen in the study are concerned, Williams suggested that “there may still be some association or correlation with increased blood flow to the frontal lobe associated with even ‘regular’ physical activity.”
“There is also likely to be some cognitive stimulation associated with the physical activity that may also play a role,” he also noted.
However, Hakun cautioned that he “would be hesitant to conjecture [regarding] any major neurobiological changes over that quick timescale,” noting that documented effects of exercise take place on a scale of “months to years.”
He suspected, instead, that the increase in processing speed has to do with changes in a person’s cognitive processing state as a result of being physically active.
He postulated that: “[It is] probably just general alertness. We do know that being alert and more ready to perform a task has advantages for focusing attention and [being] better prepared for performance in the moment.”