Aging leads to specific changes in the brain, and older adults are at a higher risk for developing dementia. Researchers are interested in finding interventions that can delay dementia and improve cognitive function. A recent study published in Aging and Disease looked at how different levels of exercise affected the hippocampal function in healthy older adults. The hippocampus is a critical part of the brain responsible for memory processing and decision making. Alzheimer’s disease, a common form of dementia, also affects the hippocampus. The study found that participants who engaged in high-intensity interval training (HIIT) saw improvement in hippocampal function and retained this improvement even up to five years after the intervention.
The study included 194 participants between the ages of 65 and 85 who were divided into three groups based on the intensity of their exercise regimen: low-intensity training, medium-intensity training, and high-intensity training. Participants underwent supervised exercise programs three days a week for six months and were tested on cognitive and hippocampal function. The results showed that the high-intensity interval training group experienced improvement in hippocampal-dependent spatial learning compared to the other two groups, which remained stable. Participants who initially performed poorly on assessments showed the most improvement in the high-intensity interval training group.
Researchers found that the high-intensity interval training group also had stable right-hand side hippocampal volume, while the other groups experienced a decrease in this brain area. Additionally, the structures of certain brain regions were in better condition in the high and medium-intensity groups compared to the low-intensity group. They also observed improved functional connectivity in the high-intensity interval training group between multiple neural networks. However, at the 12-month mark, there was no observed improvement in functional connectivity between network pairs compared to baseline in any of the groups. Changing biomarkers in the high-intensity interval group were associated with improved spatial learning, but exercise did not improve working memory or emotional recognition.
The study’s results show the potential brain benefits of exercise, particularly high-intensity interval training, for older adults. However, the research has limitations, including a small sample size and specific inclusion and exclusion criteria which may limit the generalizability of the findings. Future studies with larger sample sizes and diverse populations may provide more insights into the effects of exercise on cognitive function in older adults. Researchers also acknowledge the need for further investigation into how exercise affects working memory and if other factors, such as genetic factors, may influence a person’s response to exercise interventions.
The study has important implications for future research and clinical practice. The results suggest that HIIT can significantly improve hippocampal-dependent learning in healthy older adults, providing a non-pharmacological strategy to mitigate age-related cognitive decline. However, more research is needed to confirm these findings and explore the potential benefits of exercise interventions on cognitive health. Understanding the mechanisms by which exercise impacts brain function could lead to personalized exercise regimens tailored to individual needs and risk factors for cognitive decline in older adults.
