Department of Kinesiology, Iowa State University, Ames, Iowa 50011, USA.
Am J Prev Med. 2011 Oct;41(4 Suppl 2):S111-6. doi: 10.1016/j.amepre.2011.07.007.
Cardiovascular fitness has important implications for current and future health in children.
In this paper, criterion-referenced standards are developed for aerobic capacity (an indicator of cardiovascular fitness) based on receiver operating characteristic (ROC) curves.
The sample was drawn from participants aged 12-18 years in the National Health and Nutrition Examination Survey (1999-2002, N=1966). Subjects completed a treadmill exercise test from which maximal oxygen uptake (VO(2)max) was estimated from heart rate response. Metabolic syndrome was classified using previously published standards based on the National Cholesterol Education Program/Adult Treatment Panel III adult values at age 20 years. Using aerobic fitness z-scores as the test and metabolic syndrome as the criterion, ROC curve analysis was used to identify aerobic-capacity thresholds.
The area under the curve (AUC) value for boys (83.1%) was high, indicating good utility for detecting risk of metabolic syndrome with aerobic fitness values. The AUC for girls (77.2%) was slightly below the recommended value of 80%. Although the ROC plots identified a defensible point for classifying levels of fitness, the approach in the present study was to establish two independent thresholds, one aimed at high specificity and one aimed at high sensitivity. The resulting z values for the low- and higher-risk threshold lines were then converted back to VO(2)max estimates using published LMS (L=skewness, M=median, and S=coefficient of variation) parameters. Values at the low-risk threshold ranged from 40 to 44 mL/kg/min for boys and from 38 to 40 mL/kg/min for girls.
In summary, aerobic fitness can be used with moderate accuracy to differentiate between adolescents with and without metabolic syndrome. Age- and gender-specific aerobic-capacity thresholds for creating separate risk groups were identified using nationally representative growth percentiles.
心血管健康对儿童当前和未来的健康都有重要意义。
本研究通过受试者工作特征（ROC）曲线为有氧能力（心血管健康的一个指标）制定了基于参照标准的标准。
本研究的样本来自 1999-2002 年全国健康和营养调查（NHANES）中年龄在 12-18 岁的参与者（n=1966）。受试者完成了跑步机运动测试，根据心率反应估算最大摄氧量（VO2max）。代谢综合征的分类采用先前发表的标准，该标准基于 20 岁时国家胆固醇教育计划/成人治疗小组 III 成人值。使用有氧健康 z 分数作为测试，代谢综合征作为标准，进行 ROC 曲线分析以确定有氧能力的阈值。
男孩的曲线下面积（AUC）值（83.1%）较高，表明有氧能力值对检测代谢综合征风险有很好的应用价值。女孩的 AUC 值（77.2%）略低于 80%的推荐值。尽管 ROC 图确定了一个可辩护的分类健身水平的点，但本研究的方法是建立两个独立的阈值，一个旨在高特异性，一个旨在高灵敏度。然后使用发表的 LMS（偏度 L、中位数 M 和变异系数 S）参数将低风险和高风险阈值线的 z 值转换回 VO2max 估计值。低风险阈值的范围为男孩 40-44ml/kg/min，女孩 38-40ml/kg/min。
总之，有氧健康可以适度准确地区分患有和未患有代谢综合征的青少年。使用具有代表性的年龄和性别特定的有氧能力阈值来确定不同的风险组。
