Maximal Oxygen Uptake Is Underestimated during Incremental Testing in Hypertensive Older Adults: Findings from the HAEL Study

Purpose The present cross-sectional study aimed to investigate whether a maximal oxygen uptake (V?O2max) verification phase (VER) could improve the accuracy of a previous graded exercise test (GXT) to assess individual V?O2max in hypertensive individuals. Methods Thirty-Three older adults with hypertension (24 women) taking part in the Hypertension Approaches in the Elderly Study (NCT03264443) were recruited. Briefly, after performing a treadmill GXT to exhaustion, participants rested for 10 min and underwent a multistage VER to confirm GXT results. Individual V?O2max, RER, maximal heart rate (HRmax), and RPE were measured during both GXT and VER tests. Mean values were compared between bouts using paired sample t-Tests, and V?O2max was also compared between GXT and VER on an individual basis. Results Testing was well tolerated by all participants. Both absolute (P = 0.011) and relative (P = 0.014) V?O2max values were higher in VER than that in GXT. RER (P < 0.001) and RPE (P = 0.002) were lower in VER, whereas HRmax (P = 0.286) was not different between the two trials. Individual V?O2max comparisons revealed that 54.6% of the participants (18/33) achieved a V?O2max value that was ?3% during VER (mean = 13.5%, range = +3% to +22.1%, ES = 0.062), whereas 87.9% (29/33) of the tests would have been validated as a maximal effort if the classic criteria were used (i.e., VO2 plateau or at least two secondary criteria). Conclusion In sedentary older individuals with hypertension, GXT to exhaustion underestimated V?O2max in more than half of tested participants, even when established, but criticized criteria were used to confirm whether a maximal effort was attained. Using VER after GXT is a quick approach to assist with the verification of an individual's V?O2max.