Height-adjusted, rate-specific, single-stage step test for predicting maximal oxygen consumption.

A suitable ergometer that is generally favored for estimating maximal oxygen consumption (VO2 max) under field conditions or in environments where testing equipment is limited is the step test. Recently a mathematical model was reported to standardize the height of stepping for individuals of various heights. We designed a study to validate this model using a three-minute single-stage step test for predicting VO2 max in women. Seventeen women aged 19 to 33 performed each of three rate-specific step tests and a Bruce treadmill test. Direct measurements of VO2 max obtained from the treadmill test were correlated with the 15 second recovery heart rates after three different step tests done at stepping frequencies of 22, 26, and 30 step-ups per minute. The correlation coefficients of prediction of VO2 max from 15 second recovery pulse counts and directly measured oxygen consumption were 0.74 at 22 step-ups/min, 0.77 at 30 step-ups/min, and 0.8 at 26 step-ups/min. Each relationship was significant at the P less than .01 level. It can be concluded that the single-stage step test described in this study provides an effective predictor of VO2 max in young women and can be used when more complex methods of laboratory testing are unavailable or not feasible.