Assessing Agreement of Step Test Equations to Estimate VOmax in Korean Male and Female Youths Aged 13-18 Years

Abstract

PURPOSE To assess the agreement between maximal oxygen consumption (VO2max) measured directly when performing the maximal graded exercise test (GXT) and estimated VO2max from two different equations in Korean male and female youths aged 13-18 years. METHODS Sixty-six adolescents (15.3±1.7 years, 166.0±7.8 cm, 58. 7±10.0 kg, BMI 21.2±2.7) performed GXT on a treadmill and Astrand-Ryhming step test (AR test) to measure VO2max and VO2max estimates, respectively. The participants wore a portable device (Polar CS300) to measure heart rate (HR) during the tests. RESULTS Correlation coefficients (r) between VO2max of the equations and VO2max of the measured value were 0.321 (p<0.05) and 0.713 (P<0.01), respectively. The mean difference ranged from -0.234 mL·kg-1 ·min-1 to -3.63 mL·kg-1 ·min-1. The AR equation tended to be somewhat underestimated measured VO2max. The standard error of the estimate (SEE) ranged from 4.95 mL·kg-1 ·min-1 to 7.60 mL·kg-1 ·min-1, and the percentage error (%Error) ranged from 26.6% to 193.7%. CONCLUSIONS The results of this study suggest that the equation provides the closet agreement with directly measured VO2max in Korean male and female youths aged 13-18 years. A further study needs to develop a step test estimation equation targeting adults and elderly people in which validity and reliability are secured.

Keywords

• vomax
• equation
• step test
• validity
• youths