Incidence of the plateau at V˙O 2max is dependent on the anaerobic capacity

The purpose of this study was to address if there is an association between the plateau at V˙O (2max) and the anaerobic capacity. 9 well-trained cyclists (age 22.2 ± 3.5 yr, height 182.5 ± 5.0 cm, mass 75.7 ± 8.7 kg, V˙O (2max) 59.3 ± 4.8 ml x kg(-1) x min(-1)completed both an incremental step test of 20 W x min(-1) starting at 120 W for determination of maximal oxygen uptake (MOU) and a maximally accumulated oxygen deficit (MAOD) trial at 125% MOU for estimation of anaerobic capacity. Throughout all trials expired air was recorded on a breath-by-breath basis. A significant inverse relationship was observed between the MAOD and the Δ V˙O (2) during the final 60 s of the MOU test (r=-0.77, p=0.008). Of the 9 participants it was noted that only 4 exhibited a plateau at MOU. There were non-significant differences for V˙O (2) and the associated secondary criteria for those exhibiting a plateau and the non-plateau responders, despite a significant difference for MAOD (p=0.041) between groups. These data suggest that incidence of the plateau at MOU is dependent on anaerobic substrate metabolism and that ranges of responses reported in the literature may be a consequence of variations in anaerobic capacity amongst participants.