Isokinetic torque peak and hamstrings/quadriceps ratios in endurance athletes with anterior cruciate ligament laxity.

PURPOSE To evaluate torque and the hamstring/quadriceps ratio of the knee of athletes with and without anterior cruciate ligament laxity. METHODS Twenty-eight male athletes, 19 without anterior cruciate ligament laxity and 9 with anterior cruciate ligament laxity, were evaluated with an isokinetic machine model Cybex 770. The peak torque of quadriceps and hamstrings was compared, and the hamstring/quadriceps ratio on the constant angular speed of 60 masculine per second were also compared. RESULTS In athletes with anterior cruciate ligament laxity, the peak torque values (right and left knees) of flexors (120 +/- 15 and 116 +/- 15 Nm) and of extensors (218 +/- 36 Nm and 207 +/- 26 Nm) were not different than those of athletes without laxity (109 +/- 21 Nm and 111 +/- 22 Nm; 191 +/- 5 Nm and 188 +/- 35 Nm). The hamstring/quadriceps ratio of athletes with laxity (right: 57 +/- 6% and left: 56 +/- 8%) did not differ from those without anterior cruciate ligament laxity (right: 58 +/- 9% and left: 58 +/- 7%). CONCLUSIONS The anterior cruciate ligament laxity of long distances running athletes did not significantly alter the peak torque of flexors and of extensors or the hamstring/quadriceps ratio.