Physical activity linked to lower biological age, Lancet study finds

Physical activity reliably cuts mortality risks, yet connecting movement directly to biological aging metrics like DNA methylation clocks reveals a complex picture. A systematic review and meta-analysis published in The Lancet Healthy Longevity by J Shan and colleagues set out to evaluate this association across global data, analyzing 44 studies with 145,465 participants.

Physical Activity Correlates with Lower DNA Methylation Ages

The research team screened 34,437 articles published between January 1, 2011, and June 6, 2025, pulling from databases like Embase, PubMed, and Scopus. Out of those records, 44 studies met the criteria, encompassing 62,887 females and 82,578 males with mean ages stretching from 24.1 to 78.5 years. While higher activity levels generally pointed toward lower DNA methylation ages, many individual data points fell short of statistical significance. Seven cross-sectional studies entered the meta-analysis, prompting the authors to state that higher physical activity is significantly associated with lower biological age.

Causal proof remains elusive due to the heavy reliance on cross-sectional designs. To address this, the investigators urge that longitudinal studies and clinical trials using standardised, objectively measured physical activity are warranted to clarify dose–response relationships, and to determine whether physical activity can causally modify ageing trajectories, thereby informing precision strategies for healthy longevity.

Global Disparities in Walking Limitations

Extending healthspan requires looking beyond molecular clocks to functional independence, the focus of the prospective PURE study led by R Joundi and published in The Lancet Healthy Longevity. Tracking 150,221 adults across 25 nations from January 12, 2001, to May 6, 2019, the cohort included participants from four high-income countries, 16 middle-income nations, and five low-income countries. Over a mean follow-up of 14.5 years, new walking limitations surfaced most frequently in low-income settings at 3.34 per 100 person-years, compared to just 0.58 in China, 1.80 in other middle-income countries, and 1.31 in high-income regions.

Multistate models revealed an accelerated decline in lower-income areas. Individuals in low-income countries experienced an accelerated transition to walking limitation that was approximately 12 years earlier than those in high-income nations. Females experienced a higher probability of new walking limitations across all age groups compared to males. Modifiable risk factors—chiefly low education, obesity, hypertension, and low recreational physical activity—accounted for nearly a third of the population-level risk for walking limitations and nearly half of overall mortality.