Ruiz Jonatan R, Rizzo Nico S, Hurtig-Wennlöf Anita, Ortega Francisco B, Wärnberg Julia, Sjöström Michael
Unit for Preventive Nutrition, Department of Biosciences and Nutrition at NOVUM, Karolinska Institutet, Huddinge, Sweden.
Am J Clin Nutr. 2006 Aug;84(2):299-303. doi: 10.1093/ajcn/84.1.299.
It is unclear how the amount and intensity of physical activity (PA) are associated with cardiovascular fitness (CVF) and body fatness in children.
We aimed to examine the associations of total PA and intensity levels to CVF and fatness in children.
A cross-sectional study of 780 children aged 9-10 y from Sweden and Estonia was conducted. PA was measured by accelerometry and was expressed as min/d of total PA, moderate PA, and vigorous PA. CVF was measured with a maximal ergometer bike test and was expressed as W/kg. Body fat was derived from the sum of 5 skinfold-thickness measurements. Multiple regression analysis was used to determine the degree to which variance in CVF and body fat was explained by PA, after control for age, sex, and study location.
Lower body fat was significantly associated with higher levels of vigorous PA, but not with moderate or total PA. Those children who engaged in >40 min vigorous PA/d had lower body fat than did those who engaged in 10-18 min vigorous PA/d. Total PA, moderate PA, and vigorous PA were positively associated with CVF. Those children who engaged in >40 min vigorous PA/d had higher CVF than did those who accumulated <18 min vigorous PA/d.
The results suggest that PA of vigorous intensity may have a greater effect on preventing obesity in children than does PA of lower intensity, whereas both total and at least moderate to vigorous PA may improve children's CVF.
目前尚不清楚儿童的身体活动（PA）量和强度与心血管健康（CVF）及身体脂肪含量之间是如何关联的。
我们旨在研究儿童的总PA及其强度水平与CVF和身体脂肪之间的关联。
对来自瑞典和爱沙尼亚的780名9至10岁儿童进行了一项横断面研究。通过加速度计测量PA，并以总PA、中等强度PA和剧烈强度PA的分钟数/天来表示。通过最大运动功率自行车测试测量CVF，并以瓦特/千克表示。身体脂肪通过5个皮褶厚度测量值之和得出。在控制了年龄、性别和研究地点后，使用多元回归分析来确定PA对CVF和身体脂肪变异的解释程度。
较低的身体脂肪与较高水平的剧烈强度PA显著相关，但与中等强度PA或总PA无关。那些每天进行超过40分钟剧烈强度PA的儿童的身体脂肪低于那些每天进行10 - 18分钟剧烈强度PA的儿童。总PA、中等强度PA和剧烈强度PA均与CVF呈正相关。那些每天进行超过40分钟剧烈强度PA的儿童的CVF高于那些每天累积剧烈强度PA不足18分钟的儿童。
结果表明，与较低强度的PA相比，剧烈强度的PA对预防儿童肥胖可能有更大的作用，而总PA以及至少中等强度至剧烈强度的PA均可改善儿童的CVF。
