Objectives: To investigate the concepts of electromyographic threshold (EMGT) by iEMG signals and neuromuscular fatigue threshold concepts in trained male athletes. Methods: Nine competitive national level male rowers (21.8±4.4 years; 186.2±4.6 cm; 79.6±8.4 kg) took part in this investigation. Subjects were asked to participate in the graded exercise test to volitional exhaustion and 500m, 1000m, and 2000m all-out rowing ergometer tests on rowing ergometer. During the all tests oxygen consumption parameters, average power and integrated EMG of the musculus vastus lateralis was recorded. Results: The ventilatory threshold (VT) (248.9±26.67 W) and EMG threshold (258.89±27.13 W) were not significantly different but were significantly (p0.05). However, no relationship was detected between NMFT and VT and EMGT parameters, while significant relationship was found in VT and EMGT. All measured threshold values were significantly correlated (r>0.70; p<0.05) to the rowing ergometer performance characteristics. Conclusions: EMGT is closely related to aerobic-anaerobic transition phase as NMFT represents the local fatigue accumulation in the muscle