Department of Pediatrics, Pediatric Exercise and Genomics Research Center (PERC), University of California, Irvine School of Medicine, Irvine, California.
Scand J Med Sci Sports. 2019 Sep;29(9):1392-1401. doi: 10.1111/sms.13461. Epub 2019 Jun 3.
Physical activity and fitness are essential for healthy growth in children. The National Health and Nutrition Examination Survey (NHANES) evaluated fitness by estimating V̇O max from submaximal measurements of heart rate (HR) during graded treadmill exercise. Our aims were (a) to examine how well NHANES methodology used to estimate V̇O max correlated with actual VO max and (b) to evaluate a novel fitness metric using actual data collected during exercise and its relationship to physical activity and sedentary time, lipid profiles, and body composition.
Fifty-three adolescents completed NHANES submaximal exercise protocol and maximal graded cardiopulmonary exercise testing. We used a novel approach to quantifying fitness (Δvelocity × incline × body mass (VIM)/ΔHR slopes) and evaluated its relationship to physical activity and sedentary time using NHANES data (n = 4498). In a subset (n = 740), we compared ΔVIM/ΔHR slopes to NHANES estimated V̇O max and examined their relationship to cardiovascular risk factors (BMI percentiles and lipid levels).
Measured V̇O peak was moderately correlated with NHANES estimated V̇O max (r = 0.53, P < 0.01). Significantly higher ΔVIM/ΔHR slopes were associated with increased physical activity and decreased sedentary time. ΔVIM/ΔHR slopes were negatively associated with LDL, triglycerides, and BMI percentiles (P < 0.01). In general, the two fitness models were similar; however, ΔVIM/ΔHR was more discriminating than NHANES in quantifying the relationship between fitness and LDL levels.
We found that the NHANES estimated V̇O max accounted for approximately 28% of the variability in the measured V̇O peak. Our approach to estimating fitness (ΔVIM/ΔHR slopes) using actual data provided similar relationships to lipid levels. We suggest that fitness measurements based on actually measured data may produce more accurate assessments of fitness and, ultimately, better approaches linking exercise to health in children.
身体活动和健康对于儿童的健康成长至关重要。国家健康和营养检查调查（NHANES）通过在分级跑步机运动期间估计心率（HR）的次最大测量值来评估健身，从而估计 V̇O max。我们的目的是：（a）检查 NHANES 用于估计 V̇O max 的方法与实际 VO max 的相关性；（b）使用实际运动过程中收集的数据评估一种新的健身指标，并评估其与身体活动和久坐时间、血脂水平和身体成分的关系。
53 名青少年完成了 NHANES 次最大运动方案和最大分级心肺运动测试。我们使用一种新的方法来量化健身（Δ速度×倾斜度×体重（VIM）/ΔHR 斜率），并使用 NHANES 数据（n=4498）评估其与身体活动和久坐时间的关系。在一个子集中（n=740），我们将ΔVIM/ΔHR 斜率与 NHANES 估计的 V̇O max 进行比较，并检查它们与心血管风险因素（BMI 百分位数和血脂水平）的关系。
测量的 V̇O 峰值与 NHANES 估计的 V̇O max 中度相关（r=0.53，P<0.01）。ΔVIM/ΔHR 斜率显著升高与身体活动增加和久坐时间减少相关。ΔVIM/ΔHR 斜率与 LDL、甘油三酯和 BMI 百分位数呈负相关（P<0.01）。一般来说，两种健身模型相似；然而，ΔVIM/ΔHR 在量化健身与 LDL 水平之间的关系方面比 NHANES 更具辨别力。
我们发现，NHANES 估计的 V̇O max 解释了测量的 V̇O 峰值变化的大约 28%。我们使用实际数据估计健身（ΔVIM/ΔHR 斜率）的方法提供了与血脂水平相似的关系。我们建议，基于实际测量数据的健身测量可能会产生更准确的健身评估，最终为将运动与儿童健康联系起来提供更好的方法。
