It has been recently challenged the long-standing assumption that muscle fatigue causes exhaustion during high-intensity aerobic exercise. Indeed, in spite of a drop in maximal voluntary cycling power after exhaustive cycling exercise, evidence shows that human subjects are still able to produce immediately after exhaustion a power output three times higher than that required by the task. Some Authors have argued that the results by Marcora and Staiano failed to describe what actually happens at the point of exhaustion. In fact, the crucial power-velocity relationship was not addressed because of the different cadence between exhaustion and the following maximal voluntary cycling power assessment (around 40 vs 137 rpm). In addition, a possible recovery of power might be occurred during the 3-4 seconds time delay necessary for changing the mode of the ergometer between the two conditions. Aim of this study was to measure maximal voluntary cycling torque (MVCP) before and immediately after a time to exhaustion cycling exercise (TTE). Participants (n=11) were required to cycle at a cadence of 60 rpm during a TTE at 80% of their predetermined peak aerobic power and exhaustion was defined as the inability to maintain 60 rpm for more than 5 seconds. MVCP was measured in isokinetic mode with the cadence fixed at 60 rpm, before and immediately after the TTE avoiding any time delay between the two conditions. Maximal voluntary contraction (MVC), neural and contractile properties of the quadriceps were investigated using femoral nerve electrical stimulation before and after the MVCP pre and post TTE. Electromiography was recorded during the MVCPs and TTE. Values are means ± SD. Repeated measures ANOVA (followed up by Bonferroni test) and paired t tests were used for the analysis. All data are referred to the right leg. Peak torque during MVCP pre and post decreased by 34% but was still two times higher than the torque required by the TTE (p<0.001) (Fig 1). EMG activity of the vastus lateralis muscle during pre and post MVCP resulted unchanged (p=0.127). On the contrary, EMG at the end of TTE was found to be 49% significantly lower than that found in the MVCP post. Two minutes after the end of the MVCP post a decrease in MVC (p<0.01) with unaltered voluntary activation (p=0.150), compared to baseline values, was showed. At the same time all parameters of muscle contractile properties were significantly decreased (all p values < 0.001). According to Marcora and Staiano, these results challenge the assumption that muscle fatigue causes exhaustion during high-intensity aerobic exercise. The higher EMG activity immediately after the TTE suggests that central fatigue is far from being a factor limiting this type of aerobic exercise. These results further suggest that exercise tolerance is ultimately limited by perception of effort.