VO_2max is Reliably Measured from a Stand-Alone Graded Exercise Test in Healthy Women

Succi PJ, Benitez B, Kwak, M, Bergstrom, HC. VO_2max is Reliably Measured from a Stand-Alone Graded Exercise Test in Healthy Women. JEPonline 2022;25(4):14-25. This study determined the necessity of a verification bout in measuring maximal oxygen uptake (VO_2max) in healthy women. Ten women (22 ± 2 years) completed a familiarization trial and 2 treadmill graded exercise tests (GXT), each followed by 5 minutes of rest then a submaximal verification bout at 90% speed and 50% incline at termination of the GXT to determine V̇O_2GXT and V̇O2verification (highest V̇O2 from each testing method). Analyses included a 2-way repeated-measures ANOVA, intra-class correlation coefficients (ICC2,1), standard errors of the measurement (SEM), minimal differences (MD), and coefficients of variation (CoV). There were significant test (test 1 [T1] vs. test 2 [T2]) x method (GXT vs. verification) interactions (P=0.019). Post-hoc comparisons indicated V̇O_2GXTT1 (44.36 mL.kg-1.min-1) was greater than V̇O2verificationT1 ( 42.19 mL. kg-1. min-1) ( P=0.003), but there were no statistically significant differences between V̇O_2GXTT1 and V̇O_2GXTT2 (43.79 mL.kg-1.min-1) (P = 0.315), V̇O_2GXTT2 and V̇O_{2verification}T2 (42.47 mL.kg-1.min-1) (P = 0.056) or V̇O2verificationT1 and V̇O_{2verification}T2 (P = 0.597). V̇O_2GXT (ICC = 0.960, SEM = 1.20 mL.kg-1.min-1, MD = 3.32 mL.kg-1.min-1, CoV = 2.73%) and V̇O2verification (ICC = 0.941, SEM = 1.16 mL.kg-1 min-1, MD = 3.21 mL.kg-1.min-1, CoV = 2.75%) demonstrated excellent reliability. Based on the MD, one subject had differences for V̇O_2GXT test-retest, and V̇O2verification test-retest. No subject demonstrated V̇O2verification above V̇O_2GXT, and 2 subjects’ V̇O_2GXT exceed V̇O2verification. The mean and individual differences between V̇O_2GXT and V̇O2verification indicated that women achieved VO_2max from a stand-alone GXT without the need for a verification bout.