Early Functional Improvements Precede Time-Dependent Redox-Related DNA Methylation Changes During Combined Exercise Training in Middle-Aged and Older Women

Exercise may influence redox homeostasis and epigenetic plasticity, but longitudinal evidence linking redox-related DNA methylation to functional adaptation is limited. We examined time-dependent functional and methylation changes during 14 weeks of combined exercise training. Methods: In this single-arm longitudinal study, 45 physically inactive women participated in supervised aerobic and resistance exercise three times weekly. Functional outcomes and whole blood DNA methylation (Illumina EPIC array) were assessed at baseline and weeks 7 and 14. Repeated-measures models evaluated temporal changes, and redox-related CpGs were analyzed using limma with false-discovery-rate control. Results: Blood pressure, muscle strength, agility, and 6 min walk distance improved over time. Across different contrasts, hypomethylated CpGs were detected in CAT, SOD1, TXNRD1, TGFB1, and NFE2L2. Several CpGs remained significant after false-discovery-rate adjustment in the week-14-versus-baseline contrast. cg06295404 in SOCS1 was identified in two sequential contrasts. Methylation at cg07613405 in NFE2L2 was associated with 6 min walk distance, while exploratory public transcriptomic analyses showed concordant redox-gene expression patterns. Conclusion: Combined training was accompanied by early functional improvements and time-dependent redox-related methylation changes. Controlled studies with independent replication are needed to establish causality.