Extracurricular physical activity and telomere length in childhood: findings from the INMA study

Abstract

Background: Evidence on the link between physical activity (PA) and telomere length (TL) in childhood is scarce and inconsistent. This study examined the association between extracurricular PA at age 4 and changes in TL ranking from 4 to 8 years.

Methods: Longitudinal data from 547 children in the INMA birth cohort study (ages 4-8) were analyzed. Parent-reported extracurricular PA at age 4 was used to calculate metabolic equivalents (METs) in hours per day and categorized into tertiles (low, middle, and high). Leukocyte TL was measured at ages 4 and 8 using qPCR, with the primary outcome being the percentage change in TL ranking between ages 4 and 8. Multiple robust regression models were used for the main analyses.

Results: Children in the highest tertile of extracurricular PA (11.9-31.0 METs h/day) showed a significant 2.25% increase (95% CI: 0.01, 4.48; p = 0.04) in TL ranking between 4 and 8 years compared to the lowest tertile (2.2-7.8 METs h/day). No association was observed for moderate extracurricular PA (i.e., middle tertile) levels.

Conclusions: Higher levels of extracurricular PA were prospectively associated with TL rank changes from 4 to 8 years, suggesting its potential to reduce cellular damage and support healthy ageing.

Impact: Research shows an association between PA and TL maintenance in adults, but evidence in childhood is limited and inconsistent. This study investigates the association between extracurricular PA and changes in TL ranking in children aged 4-8 years, finding that higher PA levels are linked to increased TL ranking, possibly slowing telomere shortening. Findings support promoting PA in childhood to enhance cellular health and reduce chronic disease risk. Results can inform strategies by healthcare professionals, educators, and policymakers to encourage PA in children.