Healthcare (Commonwealth Union) – Exercise offers a short-term boost to brain function that can last through the next day, according to a new study led by UCL researchers.
While earlier laboratory studies have shown improved cognitive performance in the hours following exercise, the duration of these benefits has remained uncertain.
The study, published in the International Journal of Behavioral Nutrition and Physical Activity, analyzed data from participants aged 50 to 83. It found that individuals who engaged in more moderate-to-vigorous physical activity than usual performed better on memory tests the following day.
Spending less time sitting and achieving six or more hours of sleep were also associated with improved memory test results the next day.
Additionally, the study highlighted the role of deep (slow-wave) sleep, which modestly contributed to the connection between physical activity and next-day memory performance.
Researchers gathered data from 76 participants who wore activity trackers for eight days while completing daily cognitive assessments.
Dr. Mikaela Bloomberg, from the UCL Institute of Epidemiology & Health Care, indicated that their research shows that the positive effects of physical activity on short-term memory may last longer than previously believed—potentially extending to the following day rather than just a few hours after exercise. Getting adequate sleep, especially deep sleep, appears to further enhance these memory benefits.
Dr. Bloomberg pointed out that moderate or vigorous activity includes any movement that increases your heart rate, such as brisk walking, dancing, or climbing several flights of stairs. It does not necessarily have to involve structured exercise routines.
She further indicated that since this was a small-scale study, further research with a larger participant group is needed to confirm these findings.
In the short term, physical activity boosts blood flow to the brain and triggers the release of neurotransmitters like norepinephrine and dopamine, which support various cognitive processes.
These neurochemical effects are believed to persist for several hours post-exercise. However, researchers highlighted that some brain states associated with physical activity have more enduring impacts. For example, studies indicate that exercise can elevate mood for as long as 24 hours.
A separate study from 2016, conducted by another research group, reported increased synchrony in the hippocampus—a sign of enhanced hippocampal function, which plays a key role in memory—for up to 48 hours following high-intensity interval training (HIIT) cycling.
Professor Andrew Steptoe, from the UCL Institute of Epidemiology & Health Care, pointed out that for older adults, preserving cognitive abilities is crucial for maintaining quality of life, wellbeing, and independence. Identifying factors that influence cognitive health on a daily basis is therefore very valuable.
“This study provides evidence that the immediate cognitive benefits of exercise may last longer than we thought. It also suggests good sleep quality separately contributes to cognitive performance.
“However, we can’t establish from this study whether these short-term boosts to cognitive performance contribute to longer term cognitive health and though there is plenty of evidence to suggest physical activity might slow cognitive decline and reduce dementia risk, it’s still a matter of some debate.”
In the new study, researchers analyzed data from wrist-worn activity trackers to assess how much time participants spent being sedentary, engaging in light physical activity, and performing moderate or vigorous exercise. They also measured sleep duration and evaluated time spent in lighter stages of sleep (such as rapid eye movement, or REM sleep) and deeper slow-wave sleep.
To explore the relationship between various types of activity and cognitive performance the following day, the team adjusted for numerous factors that could potentially skew the findings, including the amount of moderate or vigorous activity participants completed on test days. Additionally, they considered participants’ average activity levels and sleep quality over the eight-day tracking period, recognizing that individuals who are consistently more active and experience better sleep quality tend to perform better on cognitive assessments.
