Cross-Validation of the Air Force Cycle Ergometer Test with Maximal Cycle Ergometer Testing

0810 The purpose of this investigation was to cross-validate the Air Force Cycle Ergometer Test (AFCET). Forty-four active duty Air Force males with the following characteristics were evaluated: age 38.2 ± 9.42 years; weight = 82.55 ± 11.89 kg; height = 178.54 ± 6.70 cm; percent fat = 13.07 ± 3.74 %; Body mass index (BMI) = 25.77 ± 2.64 kg×m2; heart rate max = 181.79 ± 9.42 beats × min−1. Criterion VO2max was determined via open circuit spirometry by a maximal cycle ergometer test (CET). The CET was performed as described by Wilmore et al. 1998, on an electromagnetically braked ergometer. The test protocol consisted of a warm-up of 50 W for 3 min, and then the workload was increased by 25 W every 2 min until exhaustion. The predicted VO2max from the AFCET was 41.36 ± 9.5 ml−1.kg−1.min−1 and the criterion value by CET was 39.13 ± 6.29 ml−1·kg−1·min−1. The cross-validation statistics for the model was: ryy = 0.67, R2 = 0.45 & SEE = 4.18 ml−1·kg−1·min−1. A paired t-test indicated that there was a significant mean difference between criterion TM and predicted values (AFCET), mean difference = 2.23 ml−1kg−1min−1, t = 2.094, p = 0.04. The Bland-Altman limits of agreement for the 95% confidence intervals were −16.41 to 11.94 ml−1kg−1min−1. The data from this study indicates a significant over-prediction of aerobic fitness by the AFCET. The Bland-Altman plots and the statistical analysis indicate that the AFCET does not accurately predict criterion VO2max values.