Age and Sex Differences in Physical Performance Among Adolescent Team Sport Athletes.

The study aimed to explore the differences in physical performance characteristics across various age groups (U14, U16, and U18) and sexes in adolescent team sport athletes. 473 adolescent Norwegian football and handball players were recruited for anthropometrical and physical performance testing. Performance improved with age in both boys and girls, showing significant differences between age categories. Across all tests, boys outperformed girls, and the sex difference doubled from U14 to U16, such as -5.1% to -10.3% for 30 m sprint, -5.6% to -9.8% for change of direction (CoD), 11% to 21% for countermovement jump (CMJ), and from 5% to 16% for relative strength. No further increase in differences between sexes was observed in the U18 age group. All age groups showed substantial intragroup variability in physical performance tests and anthropometric measures. The main findings from the study were increased sex differences from U14 to U16, but no further increase in sex difference from U16 to U18s as well as considerable individual variation in performance. Girls, maturing earlier than boys and showing less physical performance development, may benefit from earlier introduction to strength training to boost their physical development. Moreover, the considerable individual variation underscores the need for tailored individualized programs.