(CNN) — What if you could tell which of the things you do every day—walking from room to room, preparing a presentation at your desk, going up and down the stairs to fold your clothes, or going for a run around the block—help or do they hurt your brain more?
A new study attempted to answer that question by attaching activity monitors to the thighs of nearly 4,500 people in the UK and tracking their movements 24 hours a day for seven days. The researchers then examined how the participants’ behavior affected their short-term memory, problem-solving and processing skills.
Here’s the good news: People who spent “even small amounts of time in more vigorous activities, as little as 6 to 9 minutes, compared to sitting, sleeping or doing light activities, had higher cognitive scores,” said the Study author John Mitchell, a Medical Research Council PhD student at University College London’s Institute of Sport, Exercise and Health, in an email.
Moderate physical activity is generally defined as brisk walking, bicycling, or running up and down stairs. Vigorous movement, such as aerobic dancing, jogging, running, swimming, and bicycling up a hill, is what increases your heart rate and breathing.
The study, published Monday in the Journal of Epidemiology & Community Health, found that doing just under 10 minutes of moderate to vigorous exertion each day improved memory in study participants, but had its greatest impact on executive processes, such as planning and organization.
The cognitive improvement was modest, but as more time was spent doing more vigorous exercise, the benefits grew, Mitchell said.
Rock climbing is a great alternative activity for teens, especially those who aren’t into organized sports. Credit: Dedy Andrianto/E+/Getty Images
“Since we did not monitor the cognitive ability of the participants over the years, this may simply mean that those individuals who move more tend to have higher cognitive ability on average,” he said. “However, it could also imply that even minute changes in our daily lives can have downstream consequences for our cognition.”
Steven Malin, an associate professor in the Department of Kinesiology and Health at Rutgers University in New Jersey, told CNN the study provides a new perspective on how activity interacts with sedentary behavior and sleep.
“Understanding the interaction between sleep and various physical activities often goes unexamined,” said Malin, who was not involved in the new study.
While the study had some limitations, including a lack of knowledge about the health of the participants, its findings illustrate how “the accumulation of movement patterns in a day, a week, or a month is just as important—if not more so—than simply do a single exercise session,” he said.
A decline in cognition
There’s bad news, too: spending more time sleeping, sitting, or performing only light movements is linked to a negative impact on the brain. The study found that cognition decreased by 1% to 2% after replacing an equal portion of moderate-to-vigorous physical activity with eight minutes of sedentary behavior, six minutes of light intensity, or seven minutes of sleep.
“In most cases, we showed that just 7 to 10 minutes less MVPA (moderate to vigorous physical activity) was detrimental,” Mitchell said.
However, Mitchell clarified that this change is the product of an association, not cause and effect, due to the observational methods of the study.
Also, the sleep study’s findings can’t be taken at face value, he said. Good quality sleep is essential for the brain to function at peak performance.
“The evidence on the importance of sleep for cognitive performance is strong,” Mitchell said, “but there are two important caveats. First, too much sleep may be linked to lower cognitive performance.”
“Second, sleep quality may be even more important than duration. Our accelerometer devices can estimate how long people slept, but they can’t tell us how well they slept.”
Additional studies are needed to verify these findings and understand the role of each type of activity. However, Mitchell said, the study “highlights how even very modest differences in people’s daily movement (less than 10 minutes) are associated with quite real changes in our cognitive health.”
