Enhancing the efficacy of the 20 m multistage shuttle run test

Abstract

Objective: Maximal oxygen uptake ( Vo(2max)) of 44 ml kg(-1) min(-1) is an accepted criterion (Vo(2CR)) below which health and fitness for young male adults may be compromised. New algorithms validated for Vo2CR screening using the 20 m multistage shuttle run test (20mMST) were developed. Methods: Vo2max was assessed in 110 males using a stationary gas analyser in a treadmill test ( TT) and in 40 of these subjects using a portable gas analyser in the 20mMST. Vo2max predicted from the 20mMST in 70 subjects was used for cross validation. Two equations predicting Vo(2max) during 20mMST (EQ(MST)) and TT ( EQ(TT)) were developed. Results: Significant energy cost variance (ECV) was detected between TT and 20mMST ( p< 0.001), correlated significantly with subject height, and was a significant predictor of Vo2max differences between TT and 20mMST. The r(2) of EQ(MST) was 0.92 ( p< 0.001). Predicted Vo(2max) values from EQ(MST) correlated with directly measured 20mMST Vo(2max) at r = 0.96 ( p< 0.001). ANOVA detected no mean difference ( p> 0.05) between predicted and measured values. Prevalence of low fitness based on Vo(2CR) was 0.37. McNemar chi(2) indicated significant differences in sensitivity ( p< 0.001) and specificity ( p< 0.05) between the original 20mMST equation (EQ(LEG)) and EQ(TT), regarding Vo(2CR) screening. Cohen's kappa demonstrated higher agreement with TT Vo(2max) for EQ(TT) ( p< 0.001) than EQ(LEG) ( p< 0.05). TT Vo(2max) correlated with the end result of both EQ(LEG) and EQ(TT) at r = 0.75 ( p< 0.001). Unlike EQ(TT) ( p> 0.05), mean predicted Vo(2max) from EQ(LEG) was significantly higher compared to TT Vo(2max) ( p< 0.001). Conclusion: These algorithms increase the efficacy of 20mMST to accurately evaluate aspects of health and fitness.