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Updated: May 27, 2026

Assessment of Pulmonary Capillary Blood Volume, Membrane Diffusing Capacity, and Intrapulmonary Arteriovenous Anastomoses During Exercise
Published on: February 20, 2017
Achievement of VO2max criteria during a continuous graded exercise test and a verification stage performed by college
Constance M Mier1, Ryan P Alexander, Amanda L Mageean
1Human Performance Laboratory, Department of Sport and Exercise Sciences, Barry University, Miami Shores, Florida, USA. cmier@mail.barry.edu
Abstract:
The purpose of this study was to determine the incidence of meeting specific VO2max criteria and to test the effectiveness of a VO2max verification stage in college athletes. Thirty-five subjects completed a continuous graded exercise test (GXT) to volitional exhaustion. The frequency of achieving various respiratory exchange ratio (RER) and age-predicted maximum heart rate (HRmax) criteria and a VO2 plateau within 2 and 2.2 ml·kg(-1)·min(-1) (<2SD of the expected increase in VO2) were measured and tested against expected frequencies. After 10 minutes of active recovery, 10 subjects who did not demonstrate a plateau completed a verification stage performed at supramaximal intensity. From the GXT, the number of subjects meeting VO2max plateau was 5 (≤2 ml·kg(-1)·min(-1)) and 7 (≤2.2 ml·kg(-1)·min(-1)), RER criteria 34 (≥1.05), 32 (≥1.10), and 24 (≥1.15), HRmax criteria, 35 (<85%), 29 (<10 b·min(-1)) and 9 (HRmax). The VO2max and HRmax did not differ between GXT and the verification stage (53.6 ± 5.6 vs. 55.5 ± 5.6 ml·kg(-1)·min(-1) and 187 ± 7 vs. 187 ± 6 b·min(-1)); however, the RER was lower during the verification stage (1.15 ± 0.06 vs. 1.07 ± 0.07, p = 0.004). Six subjects achieved a similar VO2 (within 2.2 ml·kg(-1)·min(-1)), whereas 4 achieved a higher VO2 compared with the GXT. These data demonstrate that a continuous GXT limits the college athlete's ability to achieve VO2max plateau and certain RER and HR criteria. The use of a verification stage increases the frequency of VO2max achievement and may be an effective method to improve the accuracy of VO2max measurements in college athletes.
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