High-Intensity Exercise and Sport Type Are Associated with Lower Epigenetic Biological Age in Middle-Aged Men

Background: Epigenetic clocks based on DNA methylation can estimate biological age, providing insight into the effects of lifestyle on aging.We examined whether exercise patterns -including type of sport, training intensity, and training frequency -are associated with reduced biological age in men.We applied a saliva-based 10-CpG epigenetic clock to male participants (age 30-50, mean 41) and compared DNA methylation-predicted age (biological age) to chronological age across different exercise habit groups.Methods: Saliva DNA methylation at 10 CpG sites was measured and used to calculate biological age using a published linear model clock [1].Participants reported their primary sports (from 21 options), exercise intensity (very low to very high), and training days per week.Groups were compared for differences between chronological and biological age.Results: Overall, the cohort's average DNA methylation age was about 2.3 years lower than chronological age (mean chronological 41 vs. biological 38.7 years).Several exercise groups showed significantly lower biological ages.In 1 particular, very high intensity trainers (n=24) had a mean biological age 7 years younger than their actual age (33 vs. 40 years, p