Artefactual Incidence of V̇O2 Plateau and V̇O2max in Historical Studies: Time to Move on

Purpose: Contemporary understanding of the time course of oxygen uptake suggests that traditional discontinuous tests are of insufficient duration to elicit a fully developed V˙O2response. However, this remains to be empirically demonstrated. Thus, the aims of the present study were: (1) to investigate whether early V˙O2maxassessments underestimated actual V˙O2, and (2) to investigate whether the apparent V˙O2plateau observed in classic studies was an artefact of measuring in a non-steady state. Summary of facts and results: Twelve males (age 28 ± 7 y, 1.78 ± 0.05 m, 80 ± 11 kg) each completed a constant speed discontinuous test. The study design replicated the increasing gradient discontinuous test used by Tayloret al. (1955). V˙O2data were averaged during the 1.75–2.75 min V˙O2.Taylortime point and the final minute of each test V˙O2.Final. A paired samples t-test was used to evaluate differences in V˙O2peak.Taylorand V˙O2peak.Final. The V˙O2peak.Finalwas found to be significantly higher than V˙O2peak.Taylor(P <0.001, d = 1.18). The slope of the V˙O2response, calculated from the last completed gradient for each participant was significantly different from zero during the 1.75–2.75 min (Taylor: P = 0.009, d = 1.58; final: P = 0.02, d = 0.29). Conclusion: V˙O2plateau in historical studies was artefactual. Further investigation, without the fallacious assumptions of historical studies, may enable exercise physiologists and practitioners to determine which combination of exercise protocol and method of data acquisition is most conducive to elicit and detect a V˙O2plateau.