Methodological considerations for the determination of VO2max in healthy men.

Abstract

A square-wave verification bout to confirm maximal oxygen uptake ([Formula: see text]O2max) from a graded exercise test (GXT) has been recommended. This study ascertained if a verification bout is necessary to determine [Formula: see text]O2max in moderately trained men. Ten men (24 ± 4years) completed familiarization and two treadmill GXTs, followed by a submaximal verification bout to determine [Formula: see text]O2GXT and [Formula: see text]O2verification (highest [Formula: see text]O2 from each testing method). After completing the GXT, subjects rested for 5min then performed a verification bout at 90% speed and 50% incline at termination of the GXT. The 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 was no test (test 1 vs test 2) × method (GXT vs verification) interaction (p = 0.584), or main effect for test (p = 0.320), but there was a main effect for method (p = 0.011). The [Formula: see text]O2GXT (50.9±3.0mL·kg-1·min-1) was greater than [Formula: see text]O2verification (46.9 ± mL·kg-1·min-1). The [Formula: see text]O2GXT (ICC = 0.988, SEM = 1.0mL·kg-1 min-1, MD = 2.9mL kg-1 min-1, CoV = 2.03%) and [Formula: see text]O2verification (ICC = 0.976, SEM = 1.0mL·kg-1 min-1, MD = 2.7mL·kg-1·min-1, CoV = 2.03%) demonstrated "excellent" reliability. No subject exceeded the MD for [Formula: see text]O2GXT test-retest or for [Formula: see text]O2verification test-retest, but 50% of subjects had a [Formula: see text]O2GXT that was greater than the [Formula: see text]O2verification (> MD). While [Formula: see text]O2GXT and [Formula: see text]O2verification demonstrated excellent reliability, [Formula: see text]O2GXT from a stand-alone GXT provided higher estimates of [Formula: see text]O2 and, therefore, should be considered [Formula: see text]O2max. The lack of test-retest differences in [Formula: see text]O2GXT above the MD indicated that subjects achieved their highest [Formula: see text]O2 ([Formula: see text]O2max) from a standalone GXT. Therefore, the verification bout may not be required to confirm [Formula: see text]O2max in this population.