Introduction. Erectile dysfunction (ED) affects about 50% of males aged 40-70 years old. ED shares with atherosclerotic disease several common risk factors; therefore, it may be considered a surrogate marker of atherosclerosis. Sincephosphodiesterase-5 inhibitors are well known pharmacologic agents capable of significant improvement in ED, we designed this study to evaluate whether exercise training is of added value in patients with ED who are already on PDE-5 inhibitors. Methods. We recruited 20 male patients affected by ED with metabolic syndrome.At baseline, all patients underwent Cardio-Pulmonary Exercise Testing (CPET) and the International Index of Erectile Function (IIEF) test.After the initial evaluation, patients were subdivided into two groups: tadalafil group (group T, n=10), who were maintained only on tadalafil therapy, and a tadalafil/exercise training group (T/E group, n=10)who continued tadalafil but in addition underwent a2-month structured exercise training program. Results. Basal anthropometric characteristics of study population showed no significant differences. Although bothgroups showed at 2 months an improvement of the IIEF score, thiswas more evident in the T/E group (T group: 11.2 vs 14.2, P=0.02; T/E group: 10.8 vs 20.1, P<0.001). There was an improvement of oxygen consumption at peak exercise (VO2peak) only in the T/E group patients (T group: 13.63±2.03 vs 14.24±2.98 mL/kg/min; P=0.521; T/E group: 13.41±2.97 vs 16.58±3.17 mL/kg/min; P=0.006). A significant correlation was found between the changes in VO2peak and the modifications in IIEF score (r=0.575; P=0.001). Conclusion. Exercise training in ED patients treated with PDE-5 inhibitors is of added valuesincefurther improves ED, as evaluated by IIEF score, and increases functional capacity.