Abstract
[Purpose] The purpose of this study was to compare the thicknesses of the lateral abdominal muscles among the supine, sitting and standing postures during performance of the abdominal drawing-in manoeuvre (ADIM) or expiratory muscle training (EMT). [Subjects] Eighteen healthy men. [Methods] The subjects were measured at rest, then they performed ADIM or EMT in each of the postures in a random order. EMT was performed using the Threshold™ PEP, and the expiratory threshold was set at 15% of each subject’s maximal expiratory mouth pressure. The thicknesses of the transversus abdominis (TrA), internal oblique (IO) and external oblique (EO) muscles were measured by ultrasonography. [Results] Compared to rest, there were significant increases in TrA thickness during ADIM and EMT in the supine and standing positions, but not in the sitting position. [Conclusion] The result suggests that EMT and ADIM in the supine and standing positions are similarly effective at activating TrA.
