Xiufang Lin, Jianghua Zhou, Birong Dong
From The Center of Gerontology andGeriatrics/National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
DOI: 10.2340/16501977-2560

Objective: To investigate the effect of different levels of exercise on telomere length.
Methods: CINAHL, SPORTDiscus (EBSCO), OVID (Medline) and EMBASE databases were searched for eligible studies. Methodological quality was evaluated using the Newcastle-Ottawa Scale, and heterogeneity among the studies was assessed using the I-squared test. When heterogeneity among studies was high (I2 > 50%), a random-effects model was used (Review Manager version 5, Cochrane Collaboration, Copenhagen, Denmark); otherwise, a fixed-effects model was used.
Results: Eleven eligible studies involving 19,292 participants were included in this meta-analysis. Longer telomere length was associated with physically active individuals, with a mean difference (MD) of 0. 15 (95% confidence interval; 95% CI 0. 05, 0. 24); I2 = 99%. Longer telomere length was significantly associated with robust exercise (MD 0. 08 (95% CI 0. 04, 0. 12)); I2 = 99%, as was moderate exercise (MD 0. 07 (95% CI 0. 03, 0. 11)); I2 = 100%. Subgroup analysis revealed that longer telomere length was positively associated with exercise, regardless of sex, but was not statistically significant in elderly populations.
Conclusion: Compared with inactive individuals, telomere lengths were longer in active subjects, regardless of the intensity of exercise.

Telomeres are structures found at the end of human chromosomes that help to protect the chromosome. Telomeres become shorter with ageing and age-related diseases. This study investigated the effect of different levels of exercise on telomere length. Research databases were searched for relevant studies and these were checked for eligibility. Studies included in this meta-analysis were analysed for heterogeneity, using the random-effects or fixed-effects models. Longer telomere length was found to be associated with physically active individuals, and significantly associated with robust and moderate exercise. Subgroup analysis revealed that longer telomere length was positively associated with exercise, regardless of the person’s sex, but this was not statistically significant in elderly populations. In conclusion, compared with inactive individuals, people who were active had longer telomere lengths, regardless of the intensity of exercise.

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