Physical activity in midlife and telomere length measured in old age.
Level 3 - non-randomized controlled study
Prospective observational cohort study with 29-year follow-up
PubMed 22386580 · doi:10.1016/j.exger.2012.02.003
What was done
In the Helsinki Businessmen Study, 782 Finnish men (mean age 47 years in 1974) self-reported midlife physical activity, categorized as low (n=148), moderate (n=398), or high (n=236). After a 29-year follow-up in 2003, leukocyte telomere length (LTL) and the proportion of short telomeres (<5 kB) were measured via Southern blot in a random subcohort of surviving participants (n=204, mean age 76 years). Analyses were adjusted for baseline age, BMI, cholesterol, and smoking.
What was found
Adjusted mean LTL was significantly longer in the moderate physical activity group (8.27 kB, SE 0.05) compared to the low (8.10 kB, SE 0.07) and high (8.10 kB, SE 0.05) physical activity groups (P=0.03 between groups). The proportion of short telomeres was lowest in the moderate activity group (11.35%, SE 0.25) compared to the high (12.39%, SE 0.29) and low (12.21%, SE 0.39) groups (P=0.02 between groups).
Why it matters
This study suggests a non-linear relationship between midlife exercise and late-life cellular aging markers, indicating that moderate activity may better preserve telomere length over decades than sedentary behavior or high-intensity activity.
Limits
The study included only Finnish male businessmen, limiting generalizability to women and diverse populations. Physical activity was self-reported only at baseline with no intermediate tracking reported in the abstract. LTL was measured cross-sectionally at follow-up among survivors (n=204) rather than longitudinally, introducing survivor bias and leaving baseline LTL unknown.
Cited by
- supports A healthy lifestyle in midlife predicts longer telomeres and increased longevity decades later.