Exercise May Slow Cognitive Decline in Older Adults

A recent study conducted by researchers at the University of California San Diego and Wake Forest University has provided crucial insights into the potential of exercise as a preventive strategy against cognitive decline in older adults at risk of Alzheimer's disease. This groundbreaking research, published in the journal Alzheimer's & Dementia, emphasizes that even light physical activity could play a vital role in maintaining cognitive health among vulnerable populations.

Study Overview

The study, known as the EXERT trial (Exercise in Adults with Mild Memory Problems), is a multi-site clinical trial examining the effects of both low and moderate-high intensity exercise among sedentary adults diagnosed with amnestic mild cognitive impairment (aMCI). Individuals with aMCI experience memory complaints and objective memory decline, placing them at a heightened risk of developing Alzheimer's dementia.

The trial included a comparison group of similar individuals who received only usual care, consisting of routine health checkups and medication management. The findings from the EXERT trial revealed several significant outcomes:

• Participants engaged in both low and moderate-high intensity exercise exhibited stable cognitive function over a 12-month period.
• Exercise groups reported significantly less cognitive decline over the same timeframe when contrasted with the control group.
• Both exercise groups experienced less reduction in brain volume, particularly in areas crucial for cognitive function, including the prefrontal cortex.

Cognitive Health Implications

Approximately 16% of individuals with aMCI progress to Alzheimer's each year. This stark statistic underscores the necessity for effective interventions in this population. Dr. Aladdin Shadyab, the lead author, highlighted the significance of these findings during this critical intervention window, noting, "Together, these findings show us that even low intensity exercise may slow cognitive decline in at-risk older adults."

Design and Execution of the EXERT Trial

The EXERT trial stands out as one of the first large-scale clinical investigations to implement exercise programs partnered with local YMCA trainers, making participation more accessible for community members. This innovative approach is aimed at facilitating the implementation of exercise as a preventive measure against Alzheimer's.

As part of the trial, nearly 300 sedentary older adults were randomly assigned to either a group focusing on moderate-high intensity aerobic training or a group engaged in lower-intensity stretching, balance, and range of motion activities. Each group participated in their respective exercises three to four times weekly over a twelve-month duration, accompanied by regular cognitive assessments and brain imaging to monitor for changes in brain volume.

Significance of Findings

The findings from the EXERT trial challenge prior assumptions that senior populations would inevitably experience cognitive decline. Instead, the results indicate both low and high-intensity exercise may effectively slow this decline. Dr. Laura Baker, the principal investigator, noted the study's landmark status in examining exercise effects on cognitive health in adults with mild impairment.

“Exercise has well-documented benefits to nearly every aspect of human health, but we're still unlocking the full potential of exercise as medicine for older adults with memory problems.” – Dr. Laura Baker

Future Directions and Recommendations

Both studies within the EXERT trial highlight a pressing need to identify and implement effective interventions aimed at preventing cognitive decline during the at-risk phase. As such, the researchers conclude with several implications for future work:

• Utilizing both low and moderate-high intensity exercise programs as part of preventive care for at-risk populations.
• Incorporating community-based exercise initiatives in partnership with local organizations such as the YMCA for broader outreach.
• Conducting additional research to further elucidate the relationship between types of exercise and cognitive health outcomes.

Conclusion

The EXERT study reinforces the premise that engaging in regular physical activity, even at lower intensities, can yield significant cognitive health benefits for older adults at risk of Alzheimer's disease. The promise shown in these findings may pave the way for a new standard in Alzheimer's prevention and intervention strategies.

For further insights, readers can refer to the full study here: Medical Xpress Article.

References

[1] Baker, L. D., et al. (2025). Effects of exercise on cognition and Alzheimer's biomarkers in a randomized controlled trial of adults with mild cognitive impairment: The EXERT study, Alzheimer's & Dementia.

[2] Shadyab, A. H., et al. (2025). Effects of exercise versus usual care on older adults with amnestic mild cognitive impairment: EXERT versus ADNI, Alzheimer's & Dementia.

[3] Alzheimer's Disease Cooperative Study. Retrieved April 24, 2025.