Variation of knee angle and leg length for predicting VO sub( 2max) in healthy male volunteers using the Queen's College step test

The objective of this study was to evaluate the influence of body anthropometrics and knee joint angle (at 90 and 60 degrees) on male participants by following the Queen's College step test (QCT) and directly compare the results with VO sub( 2max). The study was designed with 38 randomly selected healthy male participants with a mean age, weight, height, body mass index (BMI), and total leg length of 20.39 years, 58.07 kg, 1.68 m, 20.33 kg.m super( -2), and 33.78 inches, respectively. Direct VO sub( 2max) of all participants was determined using the stationary bicycle exercise test and a gas analyzer. The indirect VO sub( 2max) protocol of QCT was determined by adjustable the height for knee joint flexion at an angle of either 90 or 60 degrees. The results showed that VO sub( 2max) from the indirect protocol at both 60 and 90 degrees was significantly higher and differed from the direct VO sub( 2max) protocol, with a significantly lower leg fatigue and heart rate recovery. Correlation results were significant between the direct and indirect VO sub( 2max) protocols at both 90 and 60 degrees (p< 0.01). The height, leg length, and BMI showed significant correlation with minute ventilation (VE) during direct VO sub( 2max). Whereas, VE correlated significantly with direct VO sub( 2max), when compared with both indirect QCT protocols. Finally, the leg length of all participants did not correlate with any VO sub( 2max). Therefore, this result indicated that the modification of QCT, with lower leg fatigue from different angles of the knee joint at either 90 or 60 degrees, was overestimated regarding VO sub( 2max), height, BMI, and leg length, which correlated with VE but not with the VO sub( 2max) results.