Moderate Exercise Lowers Mortality Risk Most Significantly
New 30-year twin study shows that “more” exercise may not mean “better” for longevity
Topline
A 30-year Finnish twin study finds that moderate levels of leisure-time physical activity offer the greatest longevity benefits—cutting mortality risk by 7%—while high-intensity activity offers no added survival advantage and may even accelerate biological aging.
Study Details
Researchers from the University of Jyväskylä, Finland, examined how different levels of long-term leisure-time physical activity affect mortality and biological aging. The study, published in the European Journal of Epidemiology, used a cohort of 22,750 twins born before 1958. The uniqueness of the twin-based design allowed researchers to control for genetic and shared environmental factors, adding credibility to their findings.
Methodology
Physical activity was assessed via questionnaires in 1975, 1981, and 1990, while mortality data was followed through to 2020. Participants were categorized into four groups—sedentary, moderately active, active, and highly active—based on metabolic equivalents (METs) of activity per hour per day. A subgroup of 4,897 twins also underwent epigenetic analysis to evaluate biological aging using DNA methylation "clocks."
Key Findings
Moderate physical activity was linked to the lowest mortality risk, showing a 7% reduction over 30 years.
Surprisingly, high levels of activity offered no extra mortality benefit and were associated with faster biological aging.
WHO-recommended activity levels (150–300 minutes/week) did not guarantee reduced mortality when studied in genetically matched twin pairs.
A U-shaped curve was observed: both sedentary and highly active individuals aged biologically faster than moderately active ones.
Lifestyle confounders (e.g., smoking, alcohol) and preclinical disease states may partly explain earlier research overestimating exercise benefits.
Implications for Practice
For the public: You don’t need to become an elite athlete to live longer. A consistent, moderate level of activity—like daily brisk walking, light cycling, or recreational swimming—might be optimal for longevity.
For clinicians: This study suggests tailoring exercise prescriptions toward moderation and sustainability, rather than pushing for intensity. It also highlights the importance of integrating other lifestyle factors such as diet, stress, and sleep into discussions about aging and mortality.