Alzheimer’s disease prevention may be a few workouts away, as new research hones in on how exercise affects brain health.
By Erin Miller Lo
Scientists at Rutgers University have unveiled evidence that a small increase in exercise over a short period of time could improve brain function in older adults living with prediabetes. In the study, they found that the positive effects of exercise on the brain were almost immediate, and improved with each exercise session. This is a new insight into the potential for exercise as part of a program of personalized treatments or preventions for Alzheimer’s disease–related dementia.
Alzheimer’s disease is a brain disease caused by damage to nerve cells in the brain. It is the most common cause of memory loss and reduced thinking skills. There is no cure or known prevention for the disease. Researchers around the world are continually investigating therapies that have the potential to prevent, treat, or delay Alzheimer’s disease.
Exercise, insulin, and Alzheimer’s disease
The researchers discovered that moderate exercise sessions increased the release of specialized brain cells called neuronal extracellular vesicles. These specialized cells appear to directly improve the brain’s ability to use insulin. Insulin is a hormone that regulates the body’s use of energy. It was thought for many years that insulin is not used by the brain. Scientists are now discovering that insulin does in fact enter the brain, and it regulates many central nervous system functions.
The brain’s ability to use insulin often declines in both older people and in those living with prediabetes. Prediabetes is usually caused by insulin resistance, which means the body does not use this important hormone efficiently. Insulin resistance in the brain may lead to reduced ability to think and function. With time, this reduced brain function can even lead to dementia.
Steven Malin, the Rutgers scientist who led the study, believes that this improved insulin sensitivity in the brain could reduce the risk of dementia related to Alzheimer’s disease.
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Exercise activates specialized brain cells
During the study, researchers observed 21 adults over the age of 50 who were living with prediabetes. The participants attended 12 supervised exercise sessions over two weeks. Researchers collected the participants’ blood samples before and after each session. The researchers discovered during the study that exercise contributed to improvement in brain function. This suggests that, in a very short period of time, and without a lot of extra time and effort, exercise can improve brain function among older adults with prediabetes.
Steven Malin indicated that this study is the first time that these specialized brain cells have been shown to have a positive effect on brain function. He suggested that the specialized cells can be used as a measure of the brain’s effective use of insulin. Insulin levels as a measure for brain health may be the start of prevention strategies for Alzheimer’s disease and dementia for the nearly 90 million Americans living with prediabetes and type 2 diabetes. Similarly, it may provide relief to the 5 million Americans who are living with Alzheimer’s disease and related dementia.
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Is exercise a cure for Alzheimer’s disease?
The study does indicate a strong relationship between exercise and improved insulin sensitivity in the brain. However, the researchers are careful to point out that, despite their confidence in the relationship between exercise and improved brain insulin function, they do not claim that the exercise alone caused the improvement.
This was a small study of 21 people, which means there weren’t enough people and variation in participants to apply these results to an entire population. But, the researchers’ discoveries do line up with previous research on the topic. This is enough evidence for scientists to consider it a productive research path to follow in the future.
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Future studies can help scientists expand their understanding of whether exercise and improved insulin sensitivity can protect the brain from effects of Alzheimer’s disease.
This study was published in the peer-reviewed journal Aging Cell.
References
Malin, S. K., Battillo, D. J., Beeri, M. S., Mustapic, M., Delgado-Peraza, F., & Kapogiannis, D. (2025). Two weeks of exercise alters neuronal extracellular vesicle insulin signaling proteins and pro-BDNF in older adults with prediabetes. Aging cell, 24(1), e14369. https://doi.org/10.1111/acel.14369
Alzheimer’s Association. 2024 Alzheimer’s Disease Facts and Figures. Alzheimers Dement 2024;20(5). https://www.alz.org/getmedia/76e51bb6-c003-4d84-8019-e0779d8c4e8d/alzheimers-facts-and-figures.pdf
About the Author
Erin Miller Lo (she/her) writes about scientific advances, methods, interventions, and therapeutics benefitting public health. She obtained her MPH in Health Education and Behavioral Sciences from Rutgers University, and she is based in San Diego, CA. Connect with her on BlueSky @MillerLoEJ.bsky.social.
