Effects of physical activity in telomere length: Systematic review and meta-analysis.
Level 2 - randomized trial
Systematic review and meta-analysis comprising predominantly observational and cross-sectional studies with few prospective designs
PubMed 25956165 · doi:10.1016/j.arr.2015.02.004
What was done
Authors searched MEDLINE, EMBASE, CENTRAL, Scopus, LILACS, SPORTDiscus, and Web of Science from inception through August 2014 for studies assessing the impact of exercise or physical activity on telomere length. Two independent reviewers screened records. Random-effects meta-analysis was planned where appropriate.
What was found
Across 37 original studies encompassing 41,230 participants, 20 studies observed no statistically significant association between physical activity and telomere length. Fifteen studies reported a statistically significant positive association, and two studies reported an inverted U-shaped correlation. The abstract reports no pooled numerical effect estimates.
Why it matters
Despite biological hypotheses linking exercise to reduced cellular aging, the current literature presents mixed findings, showing that physical activity cannot yet be definitively concluded to preserve or increase telomere length.
Limits
The vast majority of included studies lacked prospective designs, preventing causal inference. There was substantial methodological diversity across studies, and quantitative pooled estimates were not provided in the abstract.
Cited by
- supports The relationship between exercise volume/intensity and telomere length is non-linear, with marathon runners exhibiting only slightly longer telomeres than moderate regular runners.