The purpose of this study was to compare 2 different training modes in improving shoulder cuff muscular performance. Thirty-nine participants were randomly assigned into 3 groups: the isolated group exercised using 2-kg dumbbells; the complex group used a protocol with complex exercises; and the control group had no training. All participants trained for 6 weeks (3 times per week) and were evaluated isokinetically before (pretest) and after the training period (posttest). Results showed that the complex group significantly improved their muscular performance, but the isolated group did not, indicating that isolated exercises are only effective when the training goal is to strengthen the weaker muscle group, but they must be replaced by more complex and closed-kinetic exercises in order to obtain considerable improvement of the rotator cuff strength. The authors propose that a strengthening program should start with isolated movements for better stimulation of the weaker muscles and continue with complex exercise for more impressive strengthening.