青少年日常体力活动摄氧量预测方程的建立和检验

Establishing and Verifying the Prediction Equation of the Teenagers' Daily Physical Activities Oxygen Consumption

目的：建立更适合我国青少年的,更经济、有效的日常体力活动摄氧量方法。方法：90名11-14岁青少年随机分成实验组（60人）和验证组（30人）,男女各半。实验组以3-8km/h速度进行6个速度级别的逐级递增跑台运动,每级运动5min;以COSMED K4b2的测量值为因变量,以周岁年龄、性别、身高、体重、BMI、体脂率、瘦体重为自变量,建立回归方程;验证组在自由状态下进行运动,通过配对样本T检验用以检验预测方程的有效性,采用BlandAltman法用于检验预测方程在自由状态下预测摄氧量的系统偏差。结果：自建的预测方程为Y（m L/min）=15.404×负荷心率＋23.514×体重（kg）-194.592×性别-1735.307;男性=1,女性=2;方程R2=0.601,SEE=398.15,F检验P〈0.001,说明自变量与因变量存在线性关系,方程的拟合程度较高;自变量回归系数和常数项t检验,P〈0.001,说明自变量回归系数和常数项有意义,回归模型可靠。自建的预测方程和李海燕预测方程与实测值间均无显著性差异（P〉0.05）,自建的预测方程（男R=0.728,P〈0.001;女R=0.603,P〈0.001）与实测值存在中度相关,且相关系数均高于李海燕预测方程（男R=0.636,P〈0.001;女R=0.568,P〈0.001）;所建预测方程95%的残差均落在Bland-Altman图±1.96SD区间内,表明方程有较好的预测能力。结论：自建摄氧量预测方程有效,比同类摄氧量预测方程更经济、有效,更适用于青少年的日常体力活动摄氧量的预测。

Purpose： This study aims at establishing an economical and effective equation suitable for the measurement of the Chinese teenagers＇ oxygen consumption when doing their daily physical activities. Methods： 90 teenagers between the age of 11 to 14 were divided into two groups： the experimental（ 60） and the validation（ 30）,and each group was evenly composed of males and females. The experimental group was tested by a 6-speed-grades incremental load treadmill exercise with the beginning speed of 3 - 8km / h and each grade lasting for 5 minutes. A regression equation was established regarding the measured values of Cosmed K4b2 as dependent variables and the ages,sexes,heights,weights,BMI,body fat rate and lean body mass as the independent variables. The validation group exercised in normal conditions and the effectiveness of the predictionequation was verified by the paired-samples T test,while the Bland-Altman method was applied to check the systematic deviation of the oxygen consumption of the prediction equation in normal conditions. Results： The prediction equation can be written as： Y（ mL / min） = 15. 404 × load heart rate ＋ 23. 514 × weight（ kg）-194. 592 × sex-1735. 307; The Male = 1,The Female = 2; Equation R2 = 0. 601,SEE = 398. 15,F Verification P〈0. 001,There is no significant difference（ P〉0. 05） between the prediction equation established and Li Haiyan ＇s. There is a moderate correlation between this prediction equation（ For the male R = 0. 728,P〈0. 001; For the female R = 0. 603,P〈0. 001） and the measured values and the correlation coefficient is higher than Li Haiyan＇s（ For the male R = 0. 636,P〈0. 001; For the female R = 0. 568,P〈0. 001）. 95% residuals of this prediction equation are distributed in the ± 1. 96 SD section of the Bland-Altman graph,which indicates the better predictive ability of this equation. Conclusion： The prediction equation established for oxygen consumption is valid,which is more economical and effective than the similar ones and more suitable for the prediction of teenagers＇ oxygen consumption when doing their daily physical activities.