Effect of interferential current on deep abdominal muscle thickness

[Purpose] We aimed to investigate the effects of various modulated interferential currents on deep abdominal muscle thicknesses of healthy participants using ultrasound imaging. [Participants and Methods] We recruited twenty-two healthy male participants for this study. We compared the rate of change in muscle thickness of the abdominal muscles under different stimulation interferential current conditions. [Results] The change in interclass correlation coefficient of muscle thickness for each electrical stimulation by attached electrode altering was 0.738-0.998, indicating normal to good reliability. The rate of change for all muscle thicknesses under interferential current at 2.5 kHz and 20 Hz was significantly greater than that under the other conditions. [Conclusion] An interferential current at 2.5 kHz and 20 Hz is a feasible and reproducible way to train the abdominal muscles.