Quick Facts

• Adults aged 55-68 who exercise three times weekly for four months show significant memory improvements
• A year of 150 minutes weekly aerobic exercise makes brains look nearly one year younger
• Memory benefits decline after age 68, making earlier intervention more effective

A major 2025 analysis of 26 randomized controlled trials reveals the precise exercise prescription needed to protect memory as we age. Researchers found that exercising three times per week for at least four months produces measurable improvements in episodic memory among adults without dementia.

The systematic review, which included six studies published between 2024 and 2025, showed aerobic exercise interventions improved episodic memory with a moderate effect size. But age matters significantly for these benefits.

Age determines memory benefits

Adults aged 55 to 68 experienced significant memory improvements from exercise programs. Those aged 69 to 85 showed no significant benefits, according to the subgroup analysis.

A separate 2025 study tracked adults aged 26 to 58 for one year. Those who followed current exercise guidelines of 150 minutes per week of moderate-to-vigorous aerobic activity showed brains that appeared nearly one year younger biologically.

Optimal exercise protocols vary by type

The research identified specific protocols for maximum cognitive benefit. Resistance training works best with 12-week programs of 2-3 sessions per week lasting 45 minutes each. This approach showed the greatest improvement in global cognitive function.

For aerobic exercise targeting memory function, researchers recommend 21-week programs with twice-weekly 60-minute sessions. Earlier studies support moderate-intensity aerobic exercise at 50-70% of maximum heart rate performed 3-7 times weekly for executive function benefits.

Current guidelines support brain health

The findings align with CDC recommendations for adults 65 and older: at least 150 minutes of moderate-intensity exercise weekly plus two days of muscle-strengthening activities.

Dr. Lu Wan, lead author and data scientist at the AdventHealth Research Institute, said the research offers hopeful guidance. “We found that a simple, guideline-based exercise program can make the brain look measurably younger over just 12 months,” Wan said.

Senior researcher Binu Thomas added that starting a fitness program provides lifelong benefits for both brains and hearts, even when memory begins to fade.

Growing urgency for brain health

The research takes on added significance as the population ages. Between 2025 and 2050, adults over 65 will nearly double to 1.6 billion globally. Dementia cases are projected to rise from 57.4 million in 2019 to over 152 million by 2050.

The mechanisms behind exercise benefits include increased hippocampal volume, elevated brain-derived neurotrophic factor levels, and improved blood flow to brain regions crucial for attention and memory.

For maximum benefit, the evidence suggests starting exercise programs in middle age rather than waiting until later years, though some cognitive protection remains available for older adults who begin exercising.

Read more: How Often You Should Exercise To Support Your Memory As You Age