Bio-psycho-social correlates of physical fitness in childhood and adolescence

Abstract

Introduction: Although children and youth currently form the most active segments of the population in the westernized world, there is a<br />marked trend towards an increase in sedentary lifestyle and a decrease in physical fitness among school-age children. In order to counteract<br />the suspected degradation, potential determinants must be known. Previous studies are based on non-representative samples<br />mostly and are only conditionally comparable. Therefore, reliable findings on the determinants of physical fitness are not available. The<br />purpose of the study is the identification of correlates of physical fitness in childhood and adolescence. It is assumed that physical fitness<br />is associated with intrapersonal, behavioural and ecological factors.<br />Method: Data were obtained from the “Luxembourg project”, a representative sample of the 9, 14- and 18-year-old boys and girls from<br />Luxembourg (N = 1188). Physical fitness was measured on the basis of ten motor description categories such as aerobic endurance and<br />flexibility by using a standardised test profile. Intrapersonal (e.g. BMI, sports interest), behavioural (e.g. extent of physical activity; p.a.) and<br />ecological (e.g. peer-group behaviour, socio-economic status; ses) factors were assessed by using a standardised questionnaire (cf. Bös<br />et al., 2006).<br />Results: Ten multiple regression equations with sequential entry of the model levels help to confirm the suspected relation for eight out of<br />ten motor description categories. Percentage of declared total variance is between 8.0% (fine motor abilities on precision tasks; F=5.19;<br />p=.000; adjusted R²=.080) and 58.1% (speed of force development in lower extremities; F=67.70; p=.000; adjusted R²=.581). The identified<br />effects and their directions can be clarified by the example of gross motor abilities under time pressure (F=35.98; p=.000; adjusted<br />R²=.241). The performance in jumping sideways rises with increasing age (Beta=.64; T=17.52; p=.000), sports interest (Beta=.12; T=4.19;<br />p=.000) and ses (Beta=.10; T=3.51; p=.000) as well as under the influence of an increased extent of p.a. in sports club (Beta=.15; T=5,10;<br />p=.000), whereas lower performances become obvious with increasing BMI (Beta=-.12; T=-3.95; p=.000).<br />Perspectives<br />The results delimit the spectrum of potential correlates of physical fitness. However, the related design does not permit any causal conclusions.<br />To receive reliable statements about the determinants of motor development in childhood and adolescence, the individuals<br />included here will be examined prospectively in the context of a longitudinal section study.