Method of calculating oxygen uptake for adolescents in physical activity

Objective To establish a projection equation of oxygen uptake for Chinese adolescents in physical activity.Methods A total of 80 adolescents were randomly divided into the formula group of 60 members and the validation group of 20 members (evenly divided between male and female in each group). The task of the formula group was reaching speeds of 2,3,4,5,6,7,8 km/h in treadmill, and the duration for each level of speed was 2.5 minutes. The task of the validation group was reaching speeds of 4.8, 6.3, 8.1 km/h on the sports-ground, the duration for each level of speed was 10 minutes. In both groups were tested the gas metabolism parameters and heart rate. In the formula group was established a projection equation of oxygen uptake with the statistical method. In the validation group, the results were taken into significance test and residual analysis, while. at the speeds of 4,6,8 km/h, real-time measurement of gas metabolism back was taken, comparisons were made with the speculated values that were from the projection equation and recommended by the ACSM(American College of Sports Medicine).Results Regression equation was established for boys: oxygen uptake (mL/min) = 17.24×heart rate(bmp)+ 8.76×LBM(kg)-1288.22，for girls: oxygen uptake (mL/min) = 18.72×heart rate(bmp)+ 5.61×LBM (kg)-1588.79. The average relative errors for speculated and measured oxygen uptake in validation group were less than 10%. The SE(estimate of standard error) and E(error) were both lower than those recommended by ACSM.Conclusion According to the burden of heart rate and body weight as its independent variables, the accuracy of multiple regression equation of oxygen uptake is more reliable than that of the formula recommended by ACSM, and is more applicable for calculating oxygen uptake among Chinese adolescents in physical activity.