The purpose of the study was to compare elbow flexion peak torque (PT) and fatigue index (FI) during isokinetic concentric contractions in men and women with different training levels. Sixty-eight young men and women were divided into four groups: resistance trained men (RTM), non-resistance trained men (NRTM), resistance trained women (RTW) and non- resistance trained women (NRTW). Participants performed two tests on an isokinetic dynamometer, one to evaluate PT and one to evaluate FI. Significant interactions were found for sex and resistance training status with both PT and FI. In general, resistance-trained subjects had higher PT, and women showed lower PT than men. PT values were 67.12 ± 9.93 N·m for RTM, 49.9 ± 8.5 N·m for NRTM, 41.84 ± 7.52 N·m for RTW, and 26.05 ± 3.34 N·m for NRTW. Separate analysis revealed that RTM had higher PT than all other groups. However, FI was higher for NRTM than for RTM and NRTW and no difference was found between RTM and NRTW. FI was 37.86 ± 10.89 % for RTW, 45.74 ± 13.17 % for NTRW, 45.89 ± 8.24 % for RTM, and 51.92 ± 4.5 % for NRTM. Women produce lower PT, and have a higher fatigue tolerance than men of similar training status. Considering that women showed to be more resistant to fatigue than men, women can manipulate training variables differently from men, such as, including more repetitions at the same relative load or using higher relative loads at the same number of repetitions.