Leukocyte telomere length is preserved with aging in endurance exercise-trained adults and related to maximal aerobic capacity.

Larocca TJ, Seals DR, Pierce GL.

Department of Integrative Physiology, University of Colorado, Boulder, CO 80309, USA.

Telomere length (TL), a measure of replicative senescence, decreases with aging, but the factors involved are incompletely understood. To determine if age-associated reductions in TL are related to habitual endurance exercise and maximal aerobic exercise capacity (maximal oxygen consumption, VO(2)max), we studied groups of young (18-32 years; n=15, 7 male) and older (55-72 years; n=15, 9 male) sedentary and young (n=10, 7 male) and older (n=17, 11 male) endurance exercise-trained healthy adults. Leukocyte TL (LTL) was shorter in the older (7059+/-141bp) vs. young (8407+/-218) sedentary adults (P<0.01). LTL of the older endurance-trained adults (7992+/-169bp) was approximately 900bp greater than their sedentary peers (P<0.01) and was not significantly different (P=0.12) from young exercise-trained adults (8579+/-413). LTL was positively related to VO(2)max as a result of a significant association in older adults (r=0.44, P<0.01). Stepwise multiple regression analysis revealed that VO(2)max was the only independent predictor of LTL in the overall group. Our results indicate that LTL is preserved in healthy older adults who perform vigorous aerobic exercise and is positively related to maximal aerobic exercise capacity. This may represent a novel molecular mechanism underlying the "anti-aging" effects of maintaining high aerobic fitness.