Rapid switching from hyperbolic to isokinetic cycling allows for periodic assessment of exercise-induced fatigue through measurement of the reduction in maximal voluntary isokinetic power (MVIP). During constant-power exercise MVIP is reduced during tests above, but not below, the lactate threshold (LT) (1). During supra-LT constant-power tests MVIP decreases to a greater extent during very-heavy vs. heavy intensity exercise (1). At the limit of ramp-incremental (RI) cycle ergometry MVIP is reduced; however, the time-course is unknown. RI exercise spans all intensity domains (2); therefore, we hypothesised a progressive decrease in MVIP above LT. Characterising this time-course is likely to provide insight into the mechanisms of intolerance. Therefore, the aim of this study was to characterise the decrease in MVIP throughout a maximal RI test. Eight healthy participants (mean ± SD: age 23 ± 2 yr, height 180 ± 8 cm, mass 76 ± 8.5 kg) performed RI exercise (25 W.min-1) to the limit of tolerance to determine LT and peak oxygen uptake (VO2peak). On a separate visit (randomised), participants repeated this maximal RI test and MVIP was measured every 90 s during 6 s of isokinetic cycling at 80rpm (RI-MVIP). MVIP was also measured at baseline and instantaneously at the limit of tolerance, and breath-by-breath pulmonary gas exchange was measured throughout both tests. Lactate threshold was 1.8 ± 0.3 L.min-1. VO2peak was not different between RI protocols (3.8 ± 0.4 vs. 3.7 ± 0.5 L.min-1; p > 0.05). During RI-MVIP, below LT there was no decrease in MVIP compared to baseline (p > 0.05). In the subsequent three measures of MVIP made above LT (Post-LT 1, Post-LT 2, Post-LT 3), there was a trend for Post-LT 1 MVIP to decrease compared to baseline (Baseline vs. Post-LT 1: 836 ± 117 vs. 781 ± 136 W; p = 0.07). There was then a progressive decline in MVIP until the limit of tolerance was attained (Post-LT 1 vs. Post-LT 2 vs. Post-LT 3: 781 ± 136 vs. 712 ± 147 vs. 550 ± 151 W; all p < 0.05). At the limit of tolerance, MVIP was greater than the RI peak power (410 ± 116 vs. 285 ± 24 W; p = 0.05). The absence of a decrease in MVIP below LT is consistent with known MVIP and metabolic responses to moderate-intensity constant-power exercise (1, 3). The progressive decrease in MVIP during RI exercise above LT is consistent with the greater decline in MVIP during very-heavy vs. heavy intensity constant-power exercise (1). The time course of the decline in MVIP above LT resembles that of fatigue-related metabolite accumulation during RI exercise (4). However, the presence of a power reserve (MVIP at intolerance > RI work rate peak) suggests central fatigue is also contributory, although the specific mechanism through which peripheral and central fatigue integrate to induce task intolerance remains unknown.