[Social Differences in Physical Activity among Adolescents in Germany: Analyses Based on Information Concerning the Metabolic Equivalent of Task (MET)]

Abstract

Introduction: Energy consumption, i. e., the metabolic equivalent of task (MET), provides a precise assessment of physical activity (PA). Studies on social inequalities of PA have hardly used this possibility, however. Methods: The analyses are based on the 'Motorik-Modul (MoMo) of the KiGGS study (German Health Interview and Examination Survey for Children and Adolescents) conducted between 2003 and 2006 (n=1 757; age group 11-17 years). PA has been assessed in 3 settings (sport club in school, other sport club, leisure time). 3 dependent variables were distinguished by combining the following criteria: at least 21 MET-hours per week, intensity between 3 and 6 METs, at least 7 hours a week. The main independent variables are: type of school and socioeconomic status (SES) of the parents. 'Two part models' have been used to assess social difference in PA among those who are physically active. Results: PA is much more common in the higher SES groups. Looking at the MET-hours, though, there are just little differences among those who are physically active (regressions coefficient for low vs. high SES: 1.15; 95% conf. interv. 0.99-1.33). Conclusion: Social differences can be seen mainly for the proportion of adolescents being physically active, not for the extent of PA among those who are physically active. Therefore, the central request should be to increase the proportion of adolescents performing any PA in the low SES group.