Weight training may help keep your mind young. New research published in Gero Science Our findings suggest that older adults who engage in regular strength training can actively slow down the brain’s biological aging process. These findings provide evidence that strength-building exercise has widespread benefits for long-term cognitive health.
Scientists have consistently linked physical exercise to improved memory, sharper thinking, and lower risk of brain disease. Past research has tended to focus on how aerobic exercise, such as running or swimming, causes changes in specific isolated parts of the brain. For example, many projects focus on changes in the physical size of the hippocampus, a brain region involved in memory.
As a result, the effects of strength training on the brain as a whole have remained largely a mystery. Scientists wanted to see if weightlifting could improve overall brain health, rather than just toning specific areas. To do this, they used a sophisticated computer model called a brain clock.
Brain Clock is a mathematical tool that analyzes medical images of a person’s brain and estimates age based on biological wear and tear. If the tool estimates a lower age than a person’s actual chronological age, it suggests that the brain is aging slowly and healthily. The researchers set out to quantify exactly how a year of strength training affects this biological brain age.
“While we’ve known for years that exercise is good for the brain, most studies have focused on isolated areas (such as the hippocampus or specific networks) and have not determined whether exercise actually slows aging in the entire brain. “Resistance training is particularly understudied,” says study author Agustín Ibáñez, professor at the Global Brain Health Institute and director of the Latin American Brain Health Institute (BrainLat). Adolfo Ibáñez University.
“What we wanted to address was a very practical and urgent question: Can real-world interventions like strength training actually change the aging trajectory of the brain? To do this, we used the Brain Clock, a computational model that captures overall brain health, in a randomized trial. This allowed us to go beyond piecemeal evidence and test whether exercise affects the brain at a systems level.”
To measure these changes, the scientists first trained a brain clock model using brain scan data from 2,433 healthy adults. These scans were taken using functional magnetic resonance imaging. This technology measures brain activity by detecting changes in blood flow while a person is simply resting.
This large dataset helped computer programs learn what a typical brain network looks like at a particular age. The researchers then applied this trained brain clock to a study sample of 309 healthy older adults. These participants were between 62 and 70 years old and nearing retirement age.
Scientists randomly divided volunteers into three different groups to compare different exercise habits. The first group engaged in intense resistance training. They participated in three supervised weightlifting sessions weekly at a training center for one year.
The second group completed moderate-intensity training. This routine included one supervised session and two unsupervised home workouts each week. Exercise intensity for both groups was gradually increased over a year to safely build endurance and balance.
The third group served as a control group that did no exercise. These participants were instructed to follow their normal daily routine and avoid strenuous physical activity. All 309 participants underwent comprehensive brain scans and physical fitness tests at the beginning of the study.
The researchers tested the participants’ physical fitness by measuring their leg strength using standardized equipment. They repeated all brain scans and muscle tests after a year of training. The scientists also brought the participants back two years later for a final round of testing to see if any changes persisted.
Scientists have found that resistance training leads to significant improvements in brain connectivity. In the high-intensity training group, brain scans showed increased communication between the prefrontal cortex compared to the control group. The prefrontal cortex is an area located at the front of the brain that processes complex tasks such as planning and attention.
Analysis of brain clocks provided evidence of even broader benefits across the brain. After a one-year fitness program, we found that biological brain age decreased significantly in both the high-intensity and moderate-intensity exercise groups. On average, physical training reduced participants’ brain age by 1.4 to 2.3 years. These younger brain ages were maintained when the researchers retested the participants two years later.
“A reduction in brain age of a year or even a few months may sound modest, but it has real implications in aging research,” Ibáñez told PsyPost. “Brain aging is a slow, cumulative process, and these differences are linked to improved cognitive function, lower risk of decline, and a healthier lifespan in the future. Think of it not as a ‘quick fix,’ but as changing a long-term trajectory. Small changes, sustained over time, can have large downstream effects.”
The control group, which did not exercise, showed no significant changes in brain age over the same period.
The scientists tested specific networks, such as systems that control movement and vision, to see if the changes were isolated. They found that anti-aging effects do not come from just one network. This suggests that resistance training causes widespread reorganization of brain activity, benefiting global brain health.
“The impact was global, not local,” Ibáñez explained. “We expected changes in specific networks, but instead we saw a pattern distributed throughout the brain. This suggests that exercise does not target a single brain region, but rather works through systemic mechanisms (such as blood vessels, metabolism, and inflammatory processes).”
The researchers also looked at how physical performance changes in relation to brain age in these young people. They found a modest association between improved leg strength and decreased brain age, especially in the moderate-intensity group. This shows that improvements in physical fitness tend to go hand in hand with improvements in overall brain health.
This association did not appear in the high-intensity training group, leading scientists to suspect that it was due to a ceiling effect. Basically, more intense training does not necessarily result in a proportionally greater reduction in brain age. Even moderate amounts of physical labor can have significant biological benefits.
“The key message is simple but powerful: regular strength training can slow brain aging,” Ibáñez said. “We found that the brains of people who did (moderate or intense) resistance exercise looked about 1 to 2 years younger over time compared to people who didn’t exercise. This isn’t about elite fitness. Even moderate, consistent exercise can have measurable benefits in brain aging.”
While the findings are promising, the scientists noted some limitations to keep in mind. This study focused entirely on healthy older adults living in high-income countries in Europe. This particular demographic means that the results may not apply to people with pre-existing medical conditions or from different socio-economic backgrounds.
“An important caveat is that exercise does not ‘reverse aging’ or replace medical care,” Ibáñez noted. “Also, brain age is a probabilistic biomarker (reflecting patterns of brain health) and not a literal clock. Therefore, these results should be interpreted as evidence of increasing brain resilience, rather than as an accurate measure of turning back time.”
Future research will help reveal whether these numbers translate into significant protection against memory loss decades later. Future studies could also test these exercise programs in more diverse groups of people. Additional projects may also investigate the precise biological mechanisms linking muscle strength and brain health.
“We want to move towards precision prevention,” Ibáñez said. “It means to understand Who benefits most from which types of interventions?Integrate exercise with other factors such as , social environment, cardiovascular health, creativity, nutrition, and moderation of exposomes (environmental factors that influence health). We are also working on combining brain clocks with biological and behavioral data to more accurately predict an individual’s aging trajectory. We dream of scalable, personalized strategies for brain health for everyone. ”
The study, “A Randomized Controlled Trial of Resistance Exercise and the Brain Aging Clock,” was authored by Raul González Gómez, Niara Demnitz, Carlos Coronel, Ann Theil Gates, Michael Kjaer, Hartwig R. Siebner, Karl-Johan Boraxbeck, and Agustín M. Ibanez.
