Abstract:
Objectives: The purpose of this study was to validate the two different submaximal exercise tests, YMCA cycle ergometer test and the 3 minute step test, for predicting VO₂ max in Thais. Methods: The subjects were healthy Thais aged between 18-60 years. Two hundred and twelve men and women who passed the questionnaire screening underwent a series of exercise tests. Each subject completed a 3 minute step test, YMCA cycle test, and a maximal treadmill exercise test (GXT) with oxygen consumption measurement on a separate occasion. Results: One hundred and twenty five healthy subjects completed the study (men = 57, women = 68). There was a high correlation between predicted VO₂ max by YMCA cycle test and measured VO₂ max by GXT (r = 0.85, P < 0.001, SEE = 4.57 ml/kg/min). Predicted VO₂max by 3 minute step test had a moderate to high correlation with measured VO₂ max by GXT (r = 0.73, P < 0.001, SEE = 5.82 ml/kg/min). Thus, VO₂ max by GXT had a higher correlation with the YMCA cycle test than the 3 minute step test in Thais. In men, there was a greater correlation between measured VO₂max and estimated VO₂ max by step test (r=0.72, p < 0.001). In women, there was a greater correlation between measured VO₂ max and estimated VO₂ max by cycle (r=0.84, p is less than 0.001) than between measured VO₂ max by step test (r=0.63, P < 0.001) Conclusions: The YMCA cycle test appears to be more valid than the 3 minute step test in predicting VO₂ max in Thais. Apart from the test validity, other related factors, including test administration technique, complicated method and cost, should be taken into consideration before applying the test to the specific subjects or setting.
