The purpose of this study was to assess the VO₂max plateau response at VO₂max during a series of pre-determined trials. METHODS: Ten male well-trained athletes (age, 23.0 ± 3.2; height, 183.3 ± 5.5 cm; mass 77.5 ± 11.1 Kg; VO₂max 66.5 ± 5.0 ml^.kg^-1,min^-1), but who were VO₂max testing naïve and with prior-knowledge of trial number completed four incremental tests to volitional exhaustion, separated by ~72-h for the determination of VO₂max and gas exchange threshold. Throughout all trials VO₂max was recorded on a breath-by-breath basis using a pre-calibrated metabolic cart, using a plateau criterion of ∆ VO₂ ≤1.5 ml^.kg^-1.min^-1 over the final 2 consecutive 30 s sampling periods. A significant difference was observed between trial-1 and trial-4 for plateau incidence (p = 0.0285) rising from 20% in trial-1 to a 70% response rate in trial-4. Furthermore a significant difference was observed for VO_2dif (difference between criterion value and ∆ VO₂) in trial-1, 1.02 ± 1.69 ml^.kg^-1.min^-1 (p = 0.038), with non-significant differences observed for all other trials, despite a non-significant difference for VO₂max across all trials (p > 0.05). Finally, a significant difference was observed for effort perception (RPE) at volitional exhaustion between trial-1 (17.7 ± 1.3) and trial-4 (19.0 ± 1.4) (p = 0.0052). These data indicate that prior-knowledge of trial number can influence the manifestation of the VO₂ plateau in a group of well-trained male athletes, thereby suggesting that a form of effort control is established in order to preserve the finite anaerobic capacity.

• In well-trained athletes the incidence of plateau at VO_2max increases in conjunction with an increase in trial number and the associated sensations of pain and fatigue.

• By informing the participant of the number of trials to be completed a closed-loop condition is developed whereby effort in all trials is compared to a perceptually developed template.

• Closed-loop condition leads to a sparing of the finite anaerobic capacity during incremental tests when the number of trials to be completed is known.