We aimed to characterize female athlete's heart in elite competitors in the International Federation of Bodybuilding and Fitness (IFBB) Bikini Fitness category and compare them to athletes of a more dynamic sport discipline and healthy, sedentary volunteers using 3D echocardiography. Fifteen elite female fitness athletes were recruited and compared to 15 elite, age-matched female water polo athletes and 15 age-matched healthy, nontrained controls. Using 3D echocardiography, left ventricular (LV) and right ventricular (RV) end-diastolic volume index (EDVi) and LV mass index (LVMi) were measured. Fitness athletes presented similar LV and RV EDVi compared to healthy, sedentary volunteers. Water polo athletes, however, had higher LV and also RV EDVi (fitness versus water polo versus control; LVEDVi: 76 ± 13 versus 84 ± 8 versus 73 ± 8 ml/m2, ANOVA p = 0.045; RVEDVi: 61 ± 12 versus 86 ± 14 versus 55 ± 9 ml/m2, p < 0.0001). LVMi was significantly higher in the athlete groups; the hypertrophy, however, was even more prominent in water polo athletes (78 ± 13 versus 91 ± 10 versus 57 ± 10 g/m2, p < 0.0001). To the best of our knowledge, this is the first study to characterize female athlete's heart of IFBB Bikini Fitness competitors. The predominantly static exercise regime induced a mild, concentric-type LV hypertrophy, while in water polo athletes higher ventricular volumes and eccentric LV hypertrophy developed.