The research team used data from the 2012–2020 Health and Retirement Study and followed participants over time. Jungjoo "Jay" Lee led the project and the team compared different activity levels to determine how much and how long people must move to reduce further decline. They asked about 21 types of activities, such as walking and playing sports.
The analytic sample included 9,714 participants: 68.6% male, 31.4% female, with a median age of 78. The researchers measured cognitive decline by medical diagnosis of Alzheimer’s disease or dementia and any changes since 2012. Eight percent received a diagnosis during the study period.
The study found that people who maintained moderate physical activity had a significantly lower chance of developing dementia, while less active people saw little or no benefit. The authors noted limits, and the results may help guide new therapies and community programs. Coauthor Junhyoung "Paul" Kim highlighted walking as a simple way to support brain health.
Difficult words
- cognitive decline — A reduction in memory and thinking skills.
- dementia — A disease that affects memory and mental ability.
- diagnosis — A doctor’s statement about a health condition.
- analytic sample — The group of people used in the study.
- median age — The middle age value in the group.
- significantly — In a way that shows a real or large difference.
- maintain — To keep something at the same level.maintained
- therapy — Treatment to help heal or manage illness.therapies
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- Do you think walking is an easy exercise for older people in your area? Why or why not?
- What kinds of community programs could help older adults be more active? Give one or two ideas.
- How could doctors use these research results when they talk with older patients?
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