Researchers at the University of Jyväskylä in Jyväskylä, Finland, set out to answer this question and uncovered a surprising finding: Moderate physical activity had the most significant positive effect on longevity, reducing mortality by 7% over a 30-year period.
Interestingly, higher levels of physical activity did not confer additional mortality benefits. The study was published in the European Journal of Epidemiology.
30-Year Twin Study
The study, led by Anna Kankaanpää, postdoctoral researcher at the Gerontology Research Center (GEREC) at the Faculty of Sport and Health Sciences, University of Jyväskylä, examined 22,750 twins born before 1958. Data on leisure-time physical activity were collected from participants in 1975, 1981, and 1990, and mortality follow-up was conducted until 2020.
The researchers also investigated how physical activity influences biological aging, measured using epigenetic “clocks,” and its impact on existing risk for genetic disease.
Participants were divided into four groups based on their activity levels using a validated questionnaire that measured metabolic equivalents in h/d: Sedentary, moderately active, active, and highly active. Physical activity was assessed over a 15-year period, and mortality rates were evaluated after 30 years of follow-up.
For a subset of twins, blood samples were collected to assess biological aging using epigenetic “clocks” based on changes in DNA methylation. Genetic data were available for 4897 twins.
Exercise Guidelines — No Mortality Guarantee
The World Health Organization recommends 150-300 minutes of moderate or 75-150 minutes of vigorous physical activity per week. The researchers used these recommendations to investigate their effects on mortality and the risk for genetic diseases.
However, adherence to these recommendations does not reduce mortality or alter the risk for genetic disease. Among twin pairs in which one twin followed the guidelines for 15 years and the other did not, there was no significant difference in mortality.
The researchers suggested that potential biases in observational studies may have led to a positive association between physical activity and mortality risk. Despite accounting for various potential confounding factors and the long follow-up period, this study did not confirm this association.
Complex Lifestyle Interactions
These findings indicate that the relationship between physical activity and overall mortality is influenced by multiple interacting factors. The apparent association between leisure-time physical activity and lower mortality may reflect the participants’ overall good health and lifestyle.
The researchers speculated that an overall healthy lifestyle may have a more positive effect on biological age than the maintenance of high levels of physical activity alone.
