Validity Of A New Cardiopulmonary Exercise Test Protocol For Field Testing In Soldiers

The assessment of aerobic capacity and running performance in real-life conditions is essential for evaluating medical readiness of U.S. Service Members. There is a lack of level running field tests that can assess both maximal and submaximal indices of fitness in this population. PURPOSE: Investigate the accuracy of a new 400-meter, Continuous Progressive Aerobic Cardiovascular Endurance Run (400CPACER) test protocol in measuring maximal and submaximal indices of cardiorespiratory fitness against a standard graded exercise test on a treadmill using the Bruce protocol. METHODS: Thirty-five healthy soldiers (14.3% female) completed an exercise test to exhaustion via both the 400CPACER and Bruce protocol in random order on different days. Correlation (Pearson, r), agreement (Bland-Altman analysis), and mean differences (one-way ANOVA) between cardiorespiratory biomarkers obtained from the 400CPACER and Bruce protocols at peak exercise and the aerobic (AerT) and anaerobic (AnT) thresholds were investigated. RESULTS: Strong associations were observed between the two protocols for oxygen consumption (VO2) and heart rate (HR) at peak exercise (r = 0.81, 0.94, respectively), supported by acceptable typical percentage error (TE) (4.6% and 1.9%, respectively), and the absence of fixed, proportional biases or significant differences between protocols. Moderate correlation (r = 0.75) between protocols for VO2 was obtained at the AerT and AnT, supported by an acceptable TE (9.6% and 8.7%) and no significant difference in mean values. No fixed or proportional biases were observed in VO2 at the AnT. No significant differences (p > 0.01) in peak VO2, VO2 at the AerT, VO2 at the AnT were observed when comparing the two protocols. The 400CPACER showed higher HR at the AerT (121.4 ± 12.5 vs 133.8 ± 17.3, p < 0.01, F = 11.9) and AnT (160.7 ± 11.4 vs 169.7 ± 10.6, p < 0.01, F = 11.1), and greater time to reach peak VO2 (16.37 ± 1.46 vs 14.99 ± 1.71, p < 0.01) compared with the Bruce. CONCLUSIONS: The 400CPACER protocol accurately measured VO2 and HR at peak exercise. However, caution must be used when considering the AerT and AnT obtained via the 400CPACER protocol.