(NEWS) Strength training & brain age: RCT shows how weight training can lower biological brain age

Your brain has a biological age – and this doesn't necessarily match your chronological age. New research from the LISA randomized controlled trial offers hope: Just one year of moderate or heavy strength training can measurably reduce your biological brain age by up to 2.3 years (pFDR < 0.05). This was precisely measured using AI-powered "brain age gap" models based on approximately 2,433 fMRI datasets. Particularly noteworthy is that the rejuvenating effects are not just localized, but are evident throughout the entire brain. But what exactly is behind this mechanism – and how often do you really need to train to benefit from it?

What the LISA-RCT shows

The "Live Active Successful Aging" (LISA) study is a groundbreaking experiment that investigated whether we can slow down the aging of our brains through targeted exercise. Think of this study as a very closely monitored long-term test.

• Study type: Randomized Controlled Trial (RCT) – this is the gold standard in research, comparable to a “fair coin toss” that eliminates chance.

• Participants: 309 older adults aged 62 to 70 who had not previously engaged in regular exercise.

• Groups: The participants were divided into three groups: heavy strength training (HRT), moderate training (MIT) and a control group without training.

• Duration: The intervention lasted for one year, with follow-up examinations for up to two years.

• Measurement method: Modern fMRI scans (“cameras that film brain activity”) were used to measure the functional connectivity of the brain.

• Brain Age Gap Model: An AI model, trained on 2,433 data sets, calculated the difference between biological and chronological age ("Brain Age Gap").

• Main finding: Both moderate and heavy resistance training significantly rejuvenated the brain. The reduction in biological brain age ranged from -1.4 to -2.3 years (pFDR < 0.05).

Mechanism: How does strength training affect the brain?

You can think of the brain as a complex network of cables and routers. As we age, these connections often become "fragile" or slower – like an outdated Wi-Fi signal. Strength training acts like a comprehensive maintenance plan, renewing the hardware and increasing signal strength.

• BDNF release: Strength training stimulates brain-derived neurotrophic factor, often referred to as "fertilizer for the brain," which promotes the growth of new neurons.

• Prefrontal connectivity: Stronger connections were measured, especially in the prefrontal cortex – our center for decision-making and impulse control.

• Reduction of neuroinflammation: Chronic inflammation causes the brain to age faster; exercise has an anti-inflammatory effect.

• IGF-1 increase: Insulin-like Growth Factor 1 increases, which has neuroprotective (nerve-protecting) effects.

• Insulin sensitivity: The brain becomes more sensitive to insulin again, which improves the energy supply to the neurons.

• Vascular effects: Blood flow improves, bringing more oxygen and nutrients to remote areas of the brain.

• Global effects: The study showed that rejuvenation not only affects isolated areas, but strengthens the entire network.

• Muscle-brain axis: There was a significant correlation (r=0.12) between leg muscle strength and reduced brain age.

Dosage & Application

To achieve these neuroprotective effects, consistency is more important than intensity. The study provides clear indications of what an effective program should look like.

• Frequency: The most effective groups trained 2 to 3 times per week.

• Intensity HRT: Heavy resistance training was performed at 70–85% of the one-repetition maximum (1RM).

• Intensity MIT: Moderate Intensity Training was performed using circuit training at approximately 50% intensity.

• Exercise selection: Focus on large muscle groups (compound exercises) such as leg press, squats, deadlifts and rowing.

• Duration: The first measurable effects appeared after one year; the maximum effects (up to 2.3 years of rejuvenation) were measured after two years of consistent training.

• Progressiveness: The weight must be increased regularly ("progressive overload") to further challenge the brain and body.

• Supervision: In the study, the training was supervised, which increased compliance and safety.

For whom is strength training particularly suitable for brain health?

Not everyone benefits equally, but certain groups have a lot to gain if they start training now.

• Adults 60+: At this age, the natural decline in brain mass often begins more quickly; exercise has a preventive effect here.

• Women: Since women statistically have a higher risk of Alzheimer's and dementia, strength training is an essential protective measure for them.

• People at risk for MCI: People with "Mild Cognitive Impairment" can slow the progression through training.

• Professionals with high cognitive loads: Those who need to stay mentally fit benefit from improved prefrontal connectivity.

• Newcomers to sports: The study participants were previously inactive – so it's never too late to start.

• Responder rate: It was encouraging that approximately 75-80% of participants showed measurable improvements in the "Brain Age Gap".

Side effects & contraindications

Strength training is safe when performed correctly. However, there are points you should consider to minimize risks.

• Risk of injury: Incorrect technique poses a risk to joints and ligaments (<5% in supervised studies).

• Overtraining: Too much training without regeneration can strain the nervous system instead of strengthening it.

• Blood pressure spikes: When lifting very heavy objects (Valsalva maneuver), blood pressure can rise sharply for a short time – caution is advised for those with hypertension.

• Contraindication: Acute injuries: Fresh bone fractures or ligament tears must heal first.

• Cardiovascular diseases: In cases of severe heart disease, exercise only under medical supervision.

• Interactions: Medications such as beta-blockers can dampen the heart rate response, making exercise control more difficult.

• Medical check: A check-up is strongly recommended from the age of 50 before starting a heavy strength training program (HRT).

Limitations of the LISA-RCT

1. Limited generalizability: The study only examined healthy older adults, therefore results cannot be directly applied to sick individuals.

2. Validation of the BAG reduction: The clinical significance of the "Brain Age Gap" reduction (what does this mean specifically for everyday life?) has not yet been validated in the long term.

3. Model sensitivity: Network-specific models showed no significant differences, which could indicate a lack of sensitivity in current measurement methods.

4. Inconsistent associations: The statistical correlations between pure muscle strength and BAG reduction were relatively small and not always consistent.

5. Cultural context: The sample came from a high-income European context, which limits the generalizability to other socioeconomic groups.

⚠ Important note:

This information is for general informational purposes only and does not constitute medical advice. Strength training can increase the risk of injury – only begin new training programs after consulting a qualified medical professional, especially if you have pre-existing medical conditions. Always consult a qualified professional for any health problems.

Sources

1. Nagamatsu LS, Handy TC, Hsu CL, Voss M, Liu-Ambrose T (2012). Resistance Training Promotes Cognitive and Functional Brain Plasticity in Seniors With Probable Mild Cognitive Impairment. JAMA Internal Medicine (Arch Intern Med) ; 172(8):666-668. DOI: 10.1001/archinternmed.2012.379

2. Boraxbekk CJ, Ibanez A et al. (2026). Randomized controlled trial of resistance exercise and brain aging clocks. GeroScience . DOI: 10.1007/s11357-026-02141-x (Online ahead of print, Feb 10, 2026)

3. Mehren A et al. (2025). Neuroprotective mechanisms of exercise and the importance of fitness for healthy brain aging. The Lancet . DOI: 10.1016/S0140-6736(25)00184-9