The length of time spent in moderate-to-vigorous physical activity each day has been shown to be associated with middle-aged brain power. Journal of Epidemiology & Community Health.
This intensity level appears to be optimal for working memory and mental processes such as planning and organizing, and substituting just 6-7 minutes of light-intensity activity or sedentary behavior daily reduces cognitive performance. is shown in the survey results.
Previously published studies have linked moderate and vigorous daily physical activity (MVPA for short) to health, but few studies have included sleep, which constitutes the largest component of the 24-hour period. was, said the researchers.
Therefore, they adopted a constructive approach to investigate whether MVPA compared to all other daily exercise behaviors is optimal for middle-aged cognitive performance.
They used participants from the 1970 British Cohort Study, consisting of people born in England, Scotland, and Wales in 1970, and followed their health status from infancy through adulthood.
From 2016 to 2018, 8581 participants reached ages 46 to 47, at which point they completed detailed health, background and lifestyle questionnaires and were on activity trackers for up to 7 days and at least 10 days. was asked to wear Consecutive hours of the day.
They underwent various cognitive tests of verbal memory (immediate and delayed word retrieval tasks) and executive function (verbal fluency and processing speed/accuracy).
The scores for each test were summed to create an overall global score for memory and executive function.
Of the participants who consented to wear activity trackers, 2959 participants were excluded due to device errors, insufficient wearing time, or failure to complete the questionnaire.
The final analysis included 4481 participants, just over half (52%) of whom were women. Two-thirds (66%) were married and 43% were educated by the time she was 18.
Analysis of activity tracker data showed that participants recorded an average of 51 minutes of MVPA, 5 hours and 42 minutes of light intensity physical activity, 9 hours and 16 minutes of sedentary behavior, and 8 hours and 11 minutes of sleep over a 24-hour period. I know what I did.
Time spent on MVPA compared to other types of behavior was positively associated with cognitive performance after adjusting for educational attainment and physical activity at work. However, further adjustment for health problems weakened these associations.
Sedentary behavior compared to sleep and light physical activity was also positively associated with cognitive performance. Researchers note that this trend likely reflects more engagement in cognitively stimulating activities such as reading or working, rather than the obvious benefits of watching television.
The association was stronger for executive function than for memory.
Compared to the average across the sample, participants with the top half of cognitive performance scores spent more time on MVPA and sedentary behavior and slept less, whereas the lowest 25% of scorers had the lightest Intense physical activity was recorded.
To better understand the link between movement and cognition, researchers reallocated minutes of time from one component to another and estimated how this impacted global cognitive performance scores. Did.
This revealed that scores increased theoretically after MVPA replaced other activities.
Individual cognition showed a 1.31% improvement in cognitive ranking compared to the sample mean improvement after just 9 minutes of sedentary activity with more vigorous activity.
Similarly, replacing gentle activity improved by 1.27% and replacing 7 minutes of sleep improved by 1.2%. Such improvement was further improved by exchanging more time.
Sedentary behavior also had a positive effect on cognitive scores, but only when replaced by 37 minutes of light physical activity or 56 minutes of sleep.
Participants theoretically began to experience a 1–2% decline in cognitive ranking within the study sample after more vigorous activity was replaced by sedentary activity for as little as 8 minutes. Rankings continued to fall as MVPA fell sharply.
Similarly, replacing strenuous activity with 6 minutes of light physical activity or 7 minutes of sleep reduced cognitive ranking by 1–2%, further exacerbating MVPA loss.
Activity trackers can only record time spent in bed, not sleep duration or quality, which could help explain the link, researchers say.
“MVPA is typically the lowest percentage of the day at virtually any point in the day and is the most difficult intensity to achieve. Perhaps part of the reason for this is that even within this relatively active The loss looks harmful,” they explain.
Since this is an observational study, we cannot determine the cause. Researchers also highlight various caveats. Activity tracker measurements cannot provide context for each component of movement.Also, despite the large sample size, people of color were underrepresented, limiting the generalizability of our findings. rice field.
Nevertheless, they conclude:
Mitchell, JJ, and others. (2023) Exploring the association between daily exercise behavior and middle-aged cognition: A constructive analysis of the 1970 UK cohort study. Journal of Epidemiology & Community Health. doi.org/10.1136/jech-2022-219829.