The purpose of this study was to determine the relationship between the neuromuscular activation patterns of hip adductor longus (AL), adductor magnus (AM) and hip joint angle during isokinetic hip flexion and extension. For 9 healthy men, surface electromyography was recorded at adductor longus, adductor magnus, rectus femoris, biceps femoris, semitendinosus muscles during isokinetic hip flexion and extension by three different velocities: 60 deg/sec, 90 deg/sec and 120 deg/sec, respectively. The normalized root mean square (RMS) of AL during hip flexion was significantly higher than that of the AL during hip extension. The normalized RMS of AL during hip flexion in 10°to 40°was significantly higher than that in 60° to 70° . The normalized RMS of AM during hip extension was significantly higher than that of the AM during hip flexion. These results suggest that AL is specifically recruited at the hip shallow flexed position of hip flexion and AM is recruited during hip extension.
