The Accuracy of Non-Exercise VO2max Prediction Equations in College students
Vanesa De Santiago, John D. Smith, Ph.D.
Human Performance Laboratory, Texas A&M University-San Antonio
The non-exercising testing of VO2max is a widely used method since it is inexpensive, practical and requires very little skill. The accuracy of non-exercise prediction equations, however, needs further examination. Purpose: To determine the accuracy of two non-exercise VO2max prediction equations Methods: Forty-one participants (23 males and 18 females, age = 29.3±7 yrs, ht = 67.2±3.9 cm, wt = 85.1±23.5 kg, BMI = 28.9±6.0) successfully completed a maximal graded exercise test (GXT) where VO2max was assessed by using an open-circuit indirect calorimetry (VO2max = 35.4±8.1 ml·kg-1·min-1) as the criterion measure of VO2max using the Bruce protocol (E1). Two non-exercise prediction equations were used: one developed at U of Houston using a population of 18-70 yrs (NE1) and the other developed at BYU using a population ages 18-65 years (NE2). Data collected for both equations included the participant’s age, gender, height, weight, body mass index (BMI) using self-reported height and weight, and current physical activity (PA-R) level. Repeated measures ANOVA was used to determine the differences between non-exercise equations and the criterion, with alpha set at .05. Bland-Altman plots were used to provide an indication of agreement, and percent error was calculated as [(nonexercise–E1) / E1] X 100. Pearson’s coefficients were used to examine the relationship between the measures. Results: Significant differences existed between NE1 and E1 (38.7±8.9 and 35.3±8.0 ml·kg-1·min-1, respectively, p < .05) and NE2 and E1 (39.6±8.3 and 35.3±8.0 ml·kg-1·min-1, respectively, p < .05). This corresponded to error of 11.7±23.8% and 13.8±18.4% for NE1 and NE2, respectively. There was a significant positive correlation between NE1 and E1 (r(41) = .78, p = .001) as well as NE2 and E1 (r(41) = .63, p = .001). Conclusion: The results of the analysis indicate that caution should be used when applying the two non-exercise VO2max prediction equations for estimating VO2max in college students. While there is only a mean difference of 3.4±0.9 and 4.3±0.3 ml·kg-1·min-1 between the criterion and NE1 and NE2, respectively, the agreement as indicated by the Bland-Altman plots suggest that while the results from the equations may be accurate for some, they may not provide valid information for others.
De Santiago, Vanesa and Smith, John D.
"The Accuracy of Non-Exercise VO2max Prediction Equations in College Students,"
International Journal of Exercise Science: Conference Proceedings: Vol. 2
, Article 13.
Available at: http://digitalcommons.wku.edu/ijesab/vol2/iss4/13