Effect of Tilt Table Angle Changes on Abdominal and Lower Extremity Muscles during Passive Standing

[Purpose] The purpose of this research was to clarify the influences on abdominal muscles of tilt angle changes in passive standing on a tilt table. [Participants and Methods] The subjects were 5 healthy men. A surface electromyograph was used to measure the muscle activities of the external oblique and internal oblique abdominal muscles, and the gluteus medius, rectus femoris and biceps femoris of the right lower leg. The subjects stood on a tilt table and the tilt angles were changed for from 40° to 80° in 10° increments. Passive standing was maintained for 10 seconds at each angle and the muscle activities were measured for 3 seconds, when the wave form was stable, integrated and compared. [Results] The internal oblique muscle showed significantly high values at 40°, 70°, 80°, and at 60° its value was significantly higher than that of 50˚. No significant differences were found among the different tilt angles in the muscle activities of the external oblique, gluteus medius, rectus femoris, and biceps femoris. [Conclusion] These results show that using a tilt table at angles over 60° might be a method for selectively activating the internal oblique muscle.