DNA methylation clock DNAmFitAge shows regular exercise is associated with slower aging and systemic adaptation

DNAmPhenoAge, DNAmGrimAge, and the newly developed DNAmFitAge are DNA methylation (DNAm) based biomarkers that reflect the individual aging process. Furthermore, physical fitness is known to relate to the aging process, but its relationship to the gut microbiome has not yet been studied. Here, we examine the relationship among physical fitness, DNAm based biomarkers, and the microbiome in adults aged 33-88 with a wide range of physical fitness (including athletes with long-term training history). Higher levels of VO2max (ρ=0.2, p=6.4E-4, r=0.19, p=1.2E-3), Jumpmax p=0.11, p=5.5E-2, r=0.13 p= 2.8E-2), Gripmax (=ρ=0.17, p=3.5E-3, r=0.16, p=5.6E-3), and HDL levels (ρ=0.18, p=1.95E-3, r=0.19, p=1.1E-3) are associated with better verbal short term memory. In addition, verbal short term memory is associated with decelerated aging assessed with the new DNAm biomarker FitAgeAcceleration (ρ: −0.18, p=0.0017). DNAmFitAge is able to distinguish high fitness individuals from low/medium fitness individuals better than existing DNAm biomarkers and estimates a younger biological age in the high fit males and females (1.5 and 2.0 years younger, respectively). The microbiomal pathways are associated with VO2max, redox balance, and DNAmPhenoAge. PhenoAge Acceleration is influenced by pyruvate producing microbiomal pathways, where higher activity of these pathways lead to suppressed PhenoAge acceleration. Our research shows that regular physical exercise contributes to observable physiological, methylation, and microbiota differences which are beneficial to the aging process. DNAmFitAge emerged as a biological marker of the quality of life.