Knee flexor muscles and the vastus medialis oblique (VMO) have been suggested to play a crucial role in stabilizing the tibiofemoral and patellofemoral joints. However, those muscles have yet to be investigated for their activities across the muscle-length-velocity relationship, especially between young active female and male subjects. The purpose of this study was to determine any difference in peak torque generated by knee extensors and flexors and in the consequent iEMG amplitudes generated by VMO between females and males during voluntary isometric and isokinetic contractions. Maximum voluntary contraction of right knee flexion and extension were obtained for both isometric and isokinetic contractions in 10 young active females and 10 age- and body composition-matched males. EMG amplitudes of the vastus lateralis (VL), and rectus femoris (RF) as well as VMO were collected. The males demonstrated that knee flexor torque (Nm/kg) was significantly greater than the females at 10 and 20 deg of knee flexion during isometric contraction. The males also demonstrated that there was a significant difference in knee flexor torques in the concentric contraction of different angular velocities, whereas for the females there was no difference in these torques. In addition, the raw iEMG of VMO depended on the peak torques in isometric contraction for the males, whereas for the females it was independent of them. This study summarized differences in both isokinetic and isometric contraction between males and females, which lead to fundamental knee muscular function in the age- and body composition-matched gender.