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.