This study investigated the aerobic fitness and physiologic and energetic responses during competitive exercise in aerobic gymnasts. The gymnasts performed a graded treadmill test and competitive group exercises. Energetic response was calculated from oxygen uptake and blood lactate changes. Peak oxygen uptake was similar in International (M = 45.4 ml · kg(-1) · min.(-1), SD = 3.9) and National (M = 44.7 ml · kg(-1) · min.(-1), SD = 3.6) level groups. During their competitive routines, total energy and the fractions of aerobic, anaerobic alactic, and anaerobic lactic energy were 1,847.7 (SD = 293.9) and 1,747.3 (SD = 196.7) J · kg(-1), 53.5% (SD = 3.1) and 60.3% (SD = 6.1), 25.4% (SD = 5.9) and 21.4% (SD = 5.2), and 21.1% (SD = 5.8) and 18.3% (SD = 4.5) in international and national level athletes, respectively (p > .05). The contribution of anaerobic energy was higher in the international level group (p = .03). It is concluded that the aerobic fitness and absolute energetic and physiological responses of athletes during competitive activities were not different between the aerobic gymnasts groups with different levels of performance, but a higher relative contribution of anaerobic energy was observed in the group with a higher performance level.