Purpose <p>To investigate the effects of a fatiguing protocol on the knee extensors’ rate of torque development scaling factor (RTD-SF) during ballistic isometric contractions in physically active individuals.</p> Methods <p>The authors used a cross-over study design. Ten physically active male participated in two testing conditions: fatigue and control. Maximal voluntary isometric contraction (MVIC) was evaluated, followed by baseline and post-fatigue RTD-SF assessments using an isokinetic dynamometer. RTD-SF was evaluated with 20 knee extensor ballistic isometric contractions at four intensities: 20, 40, 60, and 80% MVIC. Three RTD-SF calculation methods and their consistencies (R²) were analyzed according to two different phases of the torque–time curve: from the onset to the 50&#xa0;ms time point, and between the 50&#xa0;ms time point and the peak torque value. The fatiguing protocol consisted of 30 maximal concentric repetitions of the knee flexors and extensors at an angular velocity of 180°·s⁻¹, with a range of motion of 90°.</p> Results <p>The absence of interaction between conditions and moments indicated no fatigability effect on RTD-SF and on its consistency, regardless of the rate of torque development (RTD) phase. The fatigue condition showed RTD-SF<i>peak</i> of 9.6 ± 3.2 and R²<i>peak</i> of 0.681 ± 0.200 at baseline, compared to RTD-SF<i>peak</i> of 9.6 ± 2.4 and R²<i>peak</i> of 0.761 ± 0.107 post-fatigue; the control condition showed RTD-SF<i>peak</i> of 10.5 ± 3.2, and R²<i>peak</i> of 0.745 ± 0.176 at baseline, compared to RTD-SF<i>peak</i> of 11.3 ± 2.6, and R²<i>peak</i> of 0.786 ± 0.133 post-rest. The other RTD-SF values for different RTD intensities followed similar trends (<i>p</i> &gt; 0.05).</p> Conclusion <p>Knee extensor RTD-SF, as well as its consistency (R²), are not affected by muscle fatigability.</p>