New 20 m Progressive Shuttle Test Protocol and Equation for Predicting the Maximal Oxygen Uptake of Korean Adolescents Aged 13-18 Years

Background: Although several equations for predicting VO_2max in children and adolescents have been reported, the validity of application of these equations to the Korean population has not been verified. The purpose of study was to develop and validate regression models to estimate maximal oxygen uptake (VO_2max) using a newly developed 20 m progressive shuttle test (20 m PST) protocol in Korean male (n = 80, 15.3 ± 1.86 years) and female (n = 81, 15.5 ± 1.73 years) adolescents aged 13-18 years. Methods: The modified 20 m PST was performed and the VO_2max was assessed in a sample of 161 participants. The participants underwent a treadmill test (TT) in the laboratory and the modified 20 m PST in a gymnasium. For the validation study, the participants performed the TT with a stationary metabolic cart and the 20 m PST with a portable metabolic cart once. In addition, they performed the 20 m PST two more times to establish test-retest reliability. Results: The mean VO_2max (49.6 ± 8.7 mL·kg^-1·min^-1) measured with the potable metabolic cart was significantly higher than that measured in the graded exercise test with the stationary metabolic cart (46.6 ± 8.9 mL·kg^-1·min^-1, p < 0.001) using the new 20 m PST protocol. The standard error of the estimate (SEE) between these two measurements was 1.35 mL·kg^-1·min^-1. However, the VO_2max derived from the newly developed equation was 46.7 ± 7.3 mL·kg^-1·min^-1 (p > 0.05) and the SEE was 2.90 mL·kg^-1·min^-1. The test and retest trials of the 20 m PST yielded comparable results (laps, r = 0.96; last speed, r = 0.93). Conclusions: Our data suggest that the new 20 m PST protocol is valid and reliable and that the equation developed in this study provides a valid estimate of VO_2max in Korean male and female adolescents aged 13-18 years.