Elite sports have become increasingly professionalized and personalized, with soccer players facing a high number of games per season. This trend presents significant challenges in optimizing training for peak performance and requires rigorous monitoring of athletes to prevent overload and reduce injury risks. The emerging field of epigenetic clocks offers promising new pathways for developing useful biomarkers to enhance training management. This study investigates the effects of intense physical activity on epigenetic age markers in professional soccer players. We analyz DNA methylation data from saliva samples collected before and after physical acctivity. Vigorous physical activity was found to have a rejuvenating effect on epigenetic clocks with significant decreases in DNAmGrimAge2 and DNAmFitAge observed immediately after games. Among player subgroups, midfielders exhibited the most substantial epigenetic rejuvenation effect following games. In addition, the study suggests a potential link between DNA methylation patterns and injury occurrence. Overall, our study suggests that DNA methylation based biomarkers may have applications in monitoring athlete performance and managing physical stress.

The Regents of the University of California are the sole owner of patents and patent applications directed at epigenetic biomarkers for which SH is a named inventor; SH is a founder and paid consultant of the non-profit Epigenetic Clock Development Foundation that licenses these patents. SH is a Principal Investigator at the Altos Labs, Cambridge Institute of Science, a biomedical company that works on rejuvenation. FP is shareholder of the DNAthlete AG. TK and MN are employees of the DNAthlete Austria GmbH.

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The study was approved by the local Ethics Committee of the Faculty of Psychology and Sport Science, Goethe-University Frankfurt/Main, Germany. The investigation was conducted according to the ethical standards set by the Declaration of Helsinki (World Medical Association Declaration of Helsinki: ethical principles for medical research involving human subjects. JAMA. 2013;310(20):2191 4. doi:10.1001/jama.2013.281053 Cited in: PubMed; PMID 24141714).

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