Abstract:
This study aimed to develop the best step test protocol which give the most accurate VO2max prediction for aerobic performance test. This research has developed 16 new step test protocols with various combination of parameters from step box height, tempo and test duration. In this study heart rate (HR) was measured by a heart rate monitor (Polar) and manual count under direct auscultation using a stethoscope. Heart rate was recorded immediately at the end of the test, and at 15 seconds, 20 seconds, and 1 minute after the test. Subjects were representative male basketball players from Thai universities. It was found in the first of study with 6 subjects under 16 new test protocols that 6 protocols were comparable to measured VO2max from gas analysis method and used for further study. In the second of study with 32 subjects, it was found that the protocol 30cm.26.3M (HR C60) with 30 cm step height at 26 steps.min-1 for 3 minutes and HR registered 1 minute after the end of the test by a stethoscope (HR C60) and with equation: Predicted VO2max = 140.66 - 0.419(HR C60 (bpm)) - 0.248(Height (cm.)) was the most accurate with respect to measured VO2max from gas analysis method (r2 = 0.714, r=0.845, SEE=2.726). While another protocol Kn.30.3M (HR P00) with an adjustable step box to achieve knee joint angle of 90 degrees at 30 steps.min-1 for three minutes and registered HR at the end of the test by the heart rate monitor (HR P00) has very high correlation with measured VO2max (equation: Predicted VO2max = 103.40 - 0.235(HRP00 (bpm)) - 0.211(Weight (kg)), r2 = 0.633, r = 0.796, SEE = 3.088). It was concluded that though 30cm.26.3M (HR C60) protocol was the most accurate, counting heart rates under direct auscultation required skillful personel. However, Kn.30.3M (HR P00) protocol used heart rate monitor that was easier and more convinient to obtain HR; thus total testing duration is reduced.