The association between aerobic fitness and physical activity in children and adolescents: the European youth heart study

Abstract

The link between aerobic fitness and physical activity in children has been studied in a number of earlier studies and the results have generally shown weak to moderate correlations. This overall finding has been widely questioned partly because of the difficulty in obtaining valid estimates of physical activity. This study investigated the cross-sectional and longitudinal relationship between aerobic fitness and physical activity in a representative sample of 9 and 15-year-old children (n = 1260 cross-sectional, n = 153 longitudinal). The specific goal was to improve past studies using an objective method of activity assessment and taking into account a number of major sources of error. Data came from the Danish part of the European youth heart study, 1997-2003. The cross-sectional results generally showed a weak to moderate association between aerobic fitness and physical activity with standardized regression coefficients ranging from 0.14 to 0.33. The longitudinal results revealed a tendency towards an interaction effect of baseline physical activity on the relationship between changes in physical activity and aerobic fitness. Moderate to moderately strong regression effect sizes were observed in the lower quadrant of baseline physical activity compared to weak effect sizes in the remaining quadrants. In conclusion, the present study confirms earlier findings of a weak to moderate association between aerobic fitness and physical activity in total population of children. However, the study also indicates that inactive children can achieve notable increase in aerobic fitness by increasing their habitual physical activity level. A potential physiological explanation for these results is highlighted.

Physical activity and physical fitness in obese, overweight, and normal-weight children

“…In addition, the authors found that initial cardiorespiratory fitness levels were a significant predictor of body weight gain. A European cross-sectional youth heart study generally showed a weak association between aerobic fitness and physical activity (20). However, the study also indicated that inactive children could achieve a notable increase in aerobic fitness by increasing their habitual level of physical activity.…”

Daily physical activity and sports participation among children from ethnic minorities in Denmark

“…Data were corrected for variation in sleeping patterns and periods when the accelerometers were not worn; data was included in the final dataset only if the monitor had recorded more than eight hours of valid recordings a day for at least three days (preschool: 4 days n=466, 3 days n=128, third grade: 4 days n=379, 3 days n=139). As cycling has been found to be associated with the amount of physical activity of Danish children and is poorly measured with accelerometers (Kristensen et al, 2010) it can distort the measured amounts of physical activity. Therefore questionnaire answers on weekly cycling habits (times per week cycling to and from school which is the main cycling activity of Danish children) were used to check and, (in case of significant differences), adjust for differences in the amount of cycling between groups.…”

Measurement agreement of FITNESSGRAM aerobic capacity and body composition standards

“…Participation in physical activity is known to lead to improvements in physical fitness but associations tend to be weaker in youth than in adolescents or adults (Morrow, 2005). Many studies have reported significant associations, but some studies have reported that genetics and maturation have a strong influence on fitness during childhood and early adolescence (Ekelund, Poortvliet, Nilsson, Yngve, Holmberg and Sjostrom, 2001;Dencker, Thorsson, Karlsson, Linden, Svensson, Wollmer and Andersen, 2006;Dencker, Thorsson, Karlsson, Linden, Wollmer and Andersen, 2008;Kristensen, Moeller, Korsholm, Kolle, Wedderkopp, Froberg and Andersen, 2010). Both physical activity and fitness have important influences on health.…”