BackgroundTelomeres are potential markers of mitotic cellular age and are associated with physical ageing process. Long-term endurance training and higher aerobic exercise capacity (VO2max) are associated with improved survival, and dynamic effects of exercise are evident with ageing. However, the association of telomere length with exercise training and VO2max has so far been inconsistent. Our aim was to assess whether muscle telomere length is associated with endurance exercise training and VO2max in younger and older people.MethodsTwenty men; 10 young (22–27 years) and 10 old (66–77 years), were studied in this cross-sectional study. Five out of 10 young adults and 5 out of 10 older were endurance athletes, while other halves were exercising at a medium level of activity. Mean telomere length was measured as telomere/single copy gene-ratio (T/S-ratio) using quantitative real time polymerase chain reaction. VO2max was measured directly running on a treadmill.ResultsOlder endurance trained athletes had longer telomere length compared with older people with medium activity levels (T/S ratio 1.12±0.1 vs. 0.92±0.2, p = 0.04). Telomere length of young endurance trained athletes was not different than young non-athletes (1.47±0.2 vs. 1.33±0.1, p = 0.12). Overall, there was a positive association between T/S ratio and VO2max (r = 0.70, p = 0.001). Among endurance trained athletes, we found a strong correlation between VO2max and T/S ratio (r = 0.78, p = 0.02). However, corresponding association among non-athlete participants was relatively weak (r = 0.58, p = 0.09).ConclusionOur data suggest that VO2max is positively associated with telomere length, and we found that long-term endurance exercise training may provide a protective effect on muscle telomere length in older people.

Although VO2peak was generally high across the age groups, VO2peak was higher in physically active adolescents of both sexes and physical activity in accordance with the recommended level may be sufficient to maintain or even increase VO2peak through adolescence.

As possible markers of biological age, telomere length (TL) has been associated with age-related diseases such as myocardial infarction (MI) with conflicting findings. We sought to assess the relationship between TL and risk of future MI in 915 healthy participants (51.7% women) 65 years or older from a population-based prospective cohort (the HUNT 2 study, Norway). Mean TL was measured by quantitative PCR expressed as relative T (telomere repeat copy number) to S (single copy gene number) ratio, and log-transformed. During a mean follow up of 13.0 (SD, 3.2) years and 11,923 person-years, 82 participants were diagnosed with MI. We used Cox proportional hazard regressions to estimate hazard ratios (HR) and 95% confidence interval (CI). Relative TL was associated with age in women (P=0.01), but not in men (P=0.43). Using relative TL as a continuous variable, we observed a higher risk of MI in participants with longer telomeres with HRs of 2.46 (95% CI; 1.13 to 4.54) in men, and 2.93 (95% CI; 1.41 to 6.10) in women. Each 1-SD change in relative TL was associated with an HR of 1.54 (95% CI; 1.15 to 2.06) and 1.67 (95% CI; 1.18 to 2.37) in men and women, respectively. Compared with the bottom tertile of relative TL, HR of incident MI in top tertile was 2.71 (95% CI; 1.25 to 5.89) in men, and 3.65 (95% CI; 1.35 to 9.90) in women. Longer telomeres in healthy participants 65 years or older are associated with a high risk of incident MI. Future large scale prospective studies are needed to confirm these findings and explore the potential association between TL and MI.

Background: Randomised trials on antibiotic treatment for patients with chronic low back pain and vertebral endplate changes visible on MRI (Modic changes) have shown mixed results. A possible explanation might be a real treatment effect in subgroups of the study populations. The purpose of the present study was to explore potential clinical effect modifiers of 3-months oral amoxicillin treatment in patients with chronic low back pain and type I or II Modic changes at the level of a previous lumbar disc herniation. Methods: We performed analyses of effect modifiers on data from AIM, a double-blind parallel-group multicentre trial. One hundred eighty patients with chronic low back pain, previous disc herniation, Modic change type I (n = 118) or type II (n = 62) were randomised to 3-months oral treatment with 750 mg amoxicillin (n = 89) or placebo (n = 91) three times daily. The primary outcome was the Roland-Morris Disability Questionnaire (RMDQ) score (possible values 0-24) at 1-year follow-up in the intention-to-treat population. The predefined minimal clinically important between-group mean difference was 4 RMDQ points (not reached in the primary analysis of AIM). Predefined baseline characteristics were analysed as potential effect modifiers, four primary (type I Modic changes, previous disc surgery, positive pain provocation test, high CRP) and five exploratory (disturbed sleep, constant low back pain, short duration of low back pain, younger age, and male) using ANCOVA with interaction terms.