Which Age Matters? Comparing Chronological and Biological Age in Adolescent Adaptation to School-Based Physical Activity Interventions (Wroclaw PEER-HEART Study).

ABSTRACT: Background/Objectives: Relative age differences within the same school year may influence adolescents' physiological adaptations to physical activity programs. While biological maturity (maturity offset, MO) is often considered a more relevant indicator than chronological age (CA), empirical evidence from school-based interventions remains limited. This study aimed to compare the predictive value of CA and MO in explaining health-related adaptations to an eight-week high-intensity interval training (HIIT) program delivered during physical education classes. Methods: A total of 256 adolescents (112 boys and 144 girls) participated in HIIT protocols integrated into regular lessons. Health-related outcomes included maximal oxygen uptake (VO₂max), body fat percentage (

SUBMITTER: Domaradzki J 

PROVIDER: S-EPMC12732137 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature