Verification testing to confirm VO2max attainment in persons with spinal cord injury

Context/Objective: Maximal oxygen uptake (VO(2)max) is a widely used measure of cardiorespiratory fitness, aerobic function, and overall health risk. Although VO(2)max has been measured for almost 100 yr, no standardized criteria exist to verify VO(2)max attainment. Studies document that incidence of 'true' VO(2)max obtained from incremental exercise (INC) can be confirmed using a subsequent verification test (VER). In this study, we examined efficacy of VER in persons with spinal cord injury (SCI). Design: Repeated measures, within-subjects study. Setting: University laboratory in San Diego, CA. Participants: Ten individuals (age and injury duration = 33.3 +/- 10.5 yr and 6.8 +/- 6.2 yr) with SCI and 10 able-bodied (AB) individuals (age = 24.1 +/- 7.4 yr). Interventions: Peak oxygen uptake (VO(2)peak) was determined during INC on an arm ergometer followed by VER at 105 percent of peak power output (% PPO). Outcome Measure: Gas exchange data, heart rate (HR), and blood lactate concentration (BLa) were measured during exercise. Results: Across all participants, VO(2)peak was highly related between protocols (ICC = 0.98) and the mean difference was equal to 0.08 +/- 0.11 L/min. Compared to INC, VO(2)peak from VER was not different in SCI (1.30 +/- 0.45 L/min vs. 1.31 +/- 0.43 L/min) but higher in AB (1.63 +/- 0.40 L/min vs. 1.76 +/- 0.40 L/min). Conclusion: Data show similar VO(2)peak between incremental and verification tests in SCI, suggesting that VER confirms VO(2)max attainment. However, in AB participants completing arm ergometry, VER is essential to validate appearance of 'true' VO(2)peak.