Neuromuscular performance characteristics in elite female athletes.

The purpose of this research was to identify possible predisposing neuromuscular factors for knee injuries, particularly anterior cruciate ligament tears in female athletes by investigating anterior knee laxity, lower extremity muscle strength, endurance, muscle reaction time, and muscle recruitment order in response to anterior tibial translation. We recruited four subject groups: elite female (N = 40) and male (N = 60) athletes and sex-matched nonathletic controls (N = 40). All participants underwent a subjective evaluation of knee function, arthrometer measurement of anterior tibial translation, isokinetic dynamometer strength and endurance tests at 60 and 240 deg/sec, and anterior tibial translation stress tests. Dynamic stress testing of muscles demonstrated less anterior tibial translation in the knees of the athletes (both men and women) compared with the nonathletic controls. Female athletes and controls demonstrated more anterior tibial laxity than their male counterparts and significantly less muscle strength and endurance. Compared with the male athletes, the female athletes took significantly longer to generate maximum hamstring muscle torque during isokinetic testing. Although no significant differences were found in either spinal or cortical muscle reaction times, the muscle recruitment order in some female athletes was markedly different. The female athletes appeared to rely more on their quadriceps muscles in response to anterior tibial translation; the three other test groups relied more on their hamstring muscles for initial knee stabilization.