Does Stronger Leg Power Protect Against Cognitive Ageing? What a 10-Year Twin Study Shows

Lower-body strength is typically associated with mobility, athletic performance, and injury prevention. However, emerging research suggests it may also play a meaningful role in long-term brain health.

While aerobic exercise is often emphasized for cognitive ageing, a 2016 longitudinal twin study raises an important question. Could greater leg power in mid-life help preserve cognitive function and brain structure over time?

A study published in the journal Gerontology examined whether baseline leg explosive power predicts cognitive ageing and brain outcomes over more than a decade.

Study Overview

This was a longitudinal observational study involving 324 healthy female twins from the TwinsUK registry, with a mean age of 55 years at baseline.

Participants completed cognitive testing using the Cambridge Neuropsychological Test Automated Battery (CANTAB) at baseline and again after 10 years. Leg explosive power was measured at baseline using the Nottingham power rig, a validated tool that assesses both force and velocity during leg extension.

The researchers applied extensive statistical adjustments for potential confounders, including:

• Cardiovascular and metabolic risk factors
• Lifestyle variables such as diet, smoking, and alcohol use
• Body composition and socioeconomic status
• Baseline cognitive ability
• Early-life factors such as birthweight

Importantly, the study included within-pair analyses in identical twins to account for shared genetics and early environmental influences. A subset of participants underwent brain MRI approximately 12 years after baseline to assess structural changes.

As an observational design, the study does not establish causation, but the twin model strengthens confidence in the observed associations.

Key Findings

The study identified a consistent relationship between leg power and long-term brain health outcomes:

Higher leg power predicted better cognitive ageing
Greater baseline leg power was significantly associated with improved cognitive performance after 10 years, even after full adjustment for confounding variables.

Preservation of brain structure
Participants with higher leg power demonstrated greater total grey matter volume on MRI years later.

Reduced markers of brain atrophy
In identical twin pairs, the twin with higher leg power showed less ventricular enlargement, suggesting reduced brain atrophy over time.

Leg power outperformed general activity measures
While self-reported physical activity showed a modest positive association, leg power emerged as the stronger and more consistent predictor.

What This Means

These findings suggest that leg muscle power, reflecting the functional capacity of the body’s largest muscle groups, may be closely linked to long-term cognitive resilience.

Several physiological mechanisms may explain this relationship:

• Release of muscle-derived signaling molecules that support brain function and reduce inflammation
• Improved vascular health and cerebral blood flow
• Maintenance of neuromuscular function, which tends to decline early with ageing
• Structural protection of the brain, reflected in preserved grey matter and reduced ventricular expansion

The use of identical twin comparisons strengthens the interpretation that this relationship is not solely driven by genetics or early-life factors. Instead, it points toward modifiable lifestyle factors, particularly those related to strength and power development.

Key Takeaways

• Greater leg explosive power in mid-life is associated with slower cognitive decline over 10 years
• Higher leg power predicts better preservation of brain structure
• The relationship persists even when controlling for genetics and early-life environment
• General physical activity contributes to brain health, but leg power appears to be a stronger marker
• Maintaining lower-body strength and power may support healthier cognitive ageing

Conclusion

This 2016 twin study provides compelling evidence that lower-body muscle power may be an important factor in long-term cognitive health. Although observational, the combination of longitudinal follow-up, twin controls, and brain imaging strengthens the case for a meaningful association.

Developing and maintaining leg power through structured resistance training and explosive movements may represent a practical strategy for supporting both physical and cognitive performance over time.

From a performance perspective, supporting this type of training requires consistent output, recovery, and neuromuscular efficiency. Creatine monohydrate remains one of the most well-supported compounds for improving strength and power, while proper hydration supports sustained performance and recovery between sessions.

Maintaining strong, powerful legs is not only relevant for athletic performance. It may also represent a long-term investment in brain health.

References

Steves, C. J., et al. (2016). Kicking Back Cognitive Ageing: Leg Power Predicts Cognitive Ageing after Ten Years in Older Female Twins. Gerontology, 62(2), 138–149. https://doi.org/10.1159/000441029

Educational Disclaimer

This post summarizes peer-reviewed scientific research for informational purposes only. It does not provide medical or nutritional advice. Always consult a qualified healthcare professional before making changes to your diet, training program, or supplementation routine, especially if you have any underlying health conditions or concerns about cognitive health.