Thirty two young soccer players were be randomly assigned to three groups: hamstring-eccentric (ECC, n=11), unstable-squatting (UNS, n=11) or control (C, n=10). The ECC and UNS groups performed eighteen sessions over 6 weeks of an injury prevention protocol, using only 3 hamstring-eccentric or unstable-squatting exercises. The angle-torque relationship was measured before and after the training intervention. Voluntary isometric torque was recorded at six test angles, with participants prone (35º-100º; 0º on full extension).