Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense M, Denmark.
Eur J Appl Physiol. 2010 Sep;110(2):267-75. doi: 10.1007/s00421-010-1491-x. Epub 2010 May 11.
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.
已有多项早期研究探讨了儿童有氧运动能力与身体活动之间的关系，结果普遍显示出弱到中度的相关性。这一总体发现受到了广泛质疑，部分原因是难以准确估计身体活动量。本研究在一个具有代表性的 9 岁和 15 岁儿童样本（横断面 1260 人，纵向 153 人）中调查了有氧运动能力与身体活动之间的横断面和纵向关系。具体目标是使用活动评估的客观方法，并考虑到许多主要误差源，改进过去的研究。数据来自于欧洲青少年心脏研究的丹麦部分，时间为 1997-2003 年。横断面研究结果普遍显示，有氧运动能力与身体活动之间存在弱到中度的关联，标准化回归系数范围为 0.14 至 0.33。纵向研究结果显示，基线身体活动对身体活动变化与有氧运动能力之间关系的交互效应存在趋势。与其余象限相比，在基线身体活动的较低四分位，观察到中等至较强的回归效应大小，而在其余象限，回归效应大小较弱。总之，本研究证实了早期研究的发现，即儿童总体人群的有氧运动能力与身体活动之间存在弱到中度的关联。然而，该研究还表明，不活跃的儿童可以通过增加其日常身体活动水平来显著提高有氧运动能力。这些结果的一个潜在生理解释被强调。
