A 15-year physical activity pattern is positively related to aerobic fitness in young males and females (13-27 years]

The purpose of this paper is to test the hypothesis that daily physical act ivity over a period of 15 years has been beneficial to aerobic fitness in y oung male and female participants (13-27 years) in the Amsterdam Growth and Health Longitudinal Study. Only subjects with the maximal data of six sets of measurements were included (83 male and 98 female participants). Daily physical activity was assessed using a standardized interview on activity a nd expressed as a weighted activity score. Aerobic fitness was assessed usi ng a maximal running test on a treadmill and measuring the maximal oxygen u ptake (VO2max) and the maximal slope of the track (S-max). To assess the lo ngitudinal relationship between daily physical activity and aerobic fitness a real longitudinal analysis was carried out with generalized estimating e quations, adjusting for differences in initial aerobic fitness at age 13, a nd for other lifestyle (dietary intake, smoking and alcohol consumption) an d biological parameters (biological age, body fat, blood pressure and conce ntration of serum cholesterol). A significant relationship (P<0.01) was obs erved between daily physical activity and both VO2max and S-max. It can be concluded that the development of aerobic fitness between the age of 13 and 27 years is independently and positively related to daily physical activit y in this group of male and female participants in the study. The functiona l implications, however, are small: a relatively high increase in the weigh ted physical activity score of 30% over a period of 15 years results in a 2 %-5% increase in aerobic fitness.