Cardiovascular fitness in adolescents: The influence of sexual maturation status—The AVENA and EYHS studies

The purposes were: (1) to determine the influence of sexual maturation status and body composition by comparing cardiovascular fitness (CVF) level in two adolescent populations from the south and the north of Europe; (2) to describe the associations between CVF and sexual maturation status in adolescence. A total of 1,867 Spanish adolescents from the AVENA study and 472 from the Swedish part of the EYHS were selected for this report (aged 14–16 years). CVF (expressed by the maximal oxygen consumption) was estimated from 20 m shuttle run test in the AVENA study and from a maximal ergometer cycle test in the EYHS. Sexual maturation status was classified according to Tanner stages. Body fat percentage (BF%) was estimated from skinfold thicknesses. Expressing CVF in different ways (in absolute value and in relation to weight or fat free mass; FFM) resulted in two different results with regard to CVF interpretation and comparison between the study populations. A higher CVF, as expressed in relation to FFM, was observed in the Spanish when compared to Swedish adolescents ( P = 0.001). However, after adjusting for both sexual maturation status and BF%, the difference disappeared in males, while it remained significant in females ( P = 0.001). CVF was negatively associated with sexual maturation status in males ( P = 0.001). However, after adjusting for BF%, the association disappeared in males, while it was significant in females ( P = 0.05). These results suggest that for CVF comparisons and interpretation in adolescent populations, sexual maturation status and BF%, as well as the way to express the CVF, should be taken into account. Am. J. Hum. Biol., 2007. © 2007 Wiley‐Liss, Inc.