Relationship between Physical Activity and Telomere Maintenance in Peripheral Blood Mononucleocytes

Shortened telomere length and decreased telomerase activity have recently been associated with perceived psychological stress and cardiovascular disease risk factors. The purpose of this study was to examine the relationship between exercise energy expenditure (EEE) and telomere length, telomerase activity, and hTERT genotype. Sixty-nine male (n = 34) and female (n = 35) participants 50-70 yr. were assessed for weekly EEE level using the exercise component of the Yale Physical Activity Survey. Lifetime consistency of EEE was also determined. Subjects were recruited across a range of EEE levels and grouped according to EEE (0-1000, 1001-3500, and >3500 Kcal/wk). Relative telomere length and telomerase activity were measured in peripheral blood mononuclear cells (PBMCs). Consistency of physical activity was the only covariate in the final model and relative telomere length was significantly higher in the Middle EEE group compared to both the low and high EEE groups (p<0.05; means ± SE relative T/S ratio; low = 0.93 ± 0.06, n=17; Middle = 1.10 ± 0.05, n=30; high = 0.94 ± 0.06, n=19). Telomerase activity was not different among the three EEE groups. An association was observed between telomerase enzyme activity and hTERT genotype with the TT genotype (1.02 x 10-2