Abstract
[Purpose] This study compared trunk muscle activities hip adduction and hip abduction during bridging exercises. [Subjects] Nine healthy individuals (5 males, 4 females) participated. [Methods] The subjects performed bridging under three conditions: with the hip in a neutral position, with hip adduction, with hip abduction. Surface electromyography was used to measure the electrical activities of the rectus abdominis, the external oblique, the multifidus, and the gluteus maximus muscles. Normalized EMG activities were compared using repeated one-way ANOVA. [Results] The EMG activities of all the muscles during bridging with hip adduction and abduction were significantly increased compared to the neutral hip position. Also, MF muscle activity was significantly higher during bridging with hip adduction than during bridging with hip abduction. GM muscle activity was significantly higher during bridging with hip abduction than during bridging with hip adduction. [Conclusion] The bridging exercise with hip adduction enhanced MF, and the bridging exercise with hip abduction enhanced GM.