hTERT Gene Expression and Athlete’s Heart: A Study in Middle-Aged Endurance Athletes

<b>Background/Objectives:</b> Telomeres and the enzyme telomerase play essential roles in cellular aging and cardiovascular health. Physical activity is thought to influence telomere dynamics via upregulation of the <i>hTERT</i> gene, which encodes the catalytic subunit of telomerase. However, data on this relationship in middle-aged endurance athletes remain limited. This study aimed to investigate the association between long-term endurance training, cardiac structural adaptations, and <i>hTERT</i> gene expression in middle-aged elite athletes. <b>Methods:</b> A total of 38 middle-aged elite runners and 37 age-matched sedentary controls were enrolled. Echocardiographic assessments, VO₂peak measurements, and <i>hTERT</i> gene expression analysis using RT-PCR were conducted. Left ventricular mass (LVM), wall thicknesses, and cardiac volumes were compared, and correlations with <i>hTERT</i> expression were analyzed. <b>Results:</b> Athletes demonstrated significantly higher VO₂peak and echocardiographic parameters including LVEDD, LV mass, and wall thicknesses (<i>p</i> < 0.05). <i>hTERT</i> gene expression was 2.06-fold higher in athletes compared to controls. Significant positive correlations were observed between <i>hTERT</i> expression and VO₂peak, LVM, LV wall thicknesses, and right ventricular parameters. <b>Conclusions:</b> These findings suggest that regular aerobic exercise may contribute to both improved cardiovascular performance and cellular longevity by enhancing telomerase-related mechanisms.