G-15E Free Communication/Slide Predicting Vo2 Max
Elliptical trainers have become very popular exercise devices and therefore are commonly found in commercial fitness centers. The elliptical trainers offer low impact aerobic exercise that can be graded over a range of intensities by changing resistance, pedal (step) rate and incline (in some models). All of these device characteristics may allow the elliptical trainer to be used for graded exercise testing.
To develop an elliptical trainer sub-maximal exercise test to predict VO2 max.
51 subjects (18–31 years) each performed two maximal treadmill exercise tests (Bruce Protocol), and three sub-maximal elliptical trainer exercise tests. The elliptical graded exercise test had the following features: 3-minute stages, incremental increases (21–25 Watts per stage) in workload and a constant cycling (step) rate of 100 per minute. The variables were: VO2 max, HR, RPE-O, workload expressed in Watts, body weight (Kg) and stage termination. HR and Watts were measured every minute of each stage, and then averaged. RPE-O was measured the second minute of each stage. A multiple linear regression analysis was conducted using the enter method on SPSS version 10.0.
Three models were chosen for further analysis. From these analyses a final formula was created in order to predict VO2 max, providing similar R, R2, and SEE values (0.724, 0.525, and 4.867) to previously reported standard sub-maximal exercise tests. The regression formula for this final model: VO2 max = 71.14 - 11.875x1 + 2.362x2 - 0.273x3 (x1=gender where 1=male, 2=female; x2 = termination stage, and x3 = weight in kg).
The elliptical trainer sub-maximal exercise test has similar validity characteristics as previously reported standard sub-maximal exercise tests that predict maximal oxygen consumption. A cross-validation study needs to be conducted on the present formula to further assess the validity of the formula and the elliptical trainer for predicting maximal oxygen consumption from a sub-maximal test.