Exercise training increases size of hippocampus and improves memory.
Level 2 - randomized trial
Individual randomized controlled trial
PubMed 21282661 · doi:10.1073/pnas.1015950108
What was done
In a randomized controlled trial of 120 older adults, investigators tested whether aerobic exercise training modifies hippocampal volume, spatial memory, and serum BDNF levels compared with a control group. Volumes of the hippocampus, caudate nucleus, and thalamus were evaluated before and after the intervention.
What was found
Aerobic exercise training increased anterior hippocampal volume by 2%, reversing age-related volume loss by 1 to 2 years, and led to improvements in spatial memory. Increased hippocampal volume was associated with higher serum levels of BDNF. In contrast, hippocampal volume declined in the control group, though higher preintervention fitness partially attenuated this decline. Caudate nucleus and thalamus volumes were unaffected by the intervention.
Why it matters
This trial demonstrates that late-adulthood hippocampal atrophy is modifiable through aerobic exercise, linking structural brain plasticity directly to improvements in memory performance.
Limits
The abstract does not specify the intervention duration, training frequency, exact age range or sex distribution of participants, or numerical effect sizes and p-values for spatial memory changes and BDNF associations. Long-term durability and impact on clinical dementia incidence were not assessed.
Cited by
- supports The volume of the hippocampus declines by approximately 1% to 2% per year in older adults.
- supports In a randomized trial, adults assigned to walk 3 to 4 times a week for 40 minutes showed a 1% increase in hippocampal volume and improved memory after one year compared to a stretching control group.