The effects of abdominal drawing-in maneuver during stair climbing on muscle activities of the trunk and legs

The purpose of this study was to investigate effects of abdominal drawing-in maneuver (ADIM) on the muscular activity of the trunk and the lower limbs during stair ascent. The subjects were healthy 15 men and 8 women who were in their 20s. After maintaining ADIM by using a pressure biofeedback unit for 15 min, the subjects performed stair ascent and their muscular activity of the right trunk and the legs was measured to determine difference between when the subjects maintained ADIM and did not. The activities of the sternocleidomastoid, the splenius capitis, the rectus abdominis (ABD), the external abdominal oblique (EO), the transverse abdominis (TRA), the elector spinae (ES), the vastus medialis (VM), and the vastus lateralis (VL) were measured using surface electromyogram (TM DTS). The collected data were statistically processed by the SPSS ver. 18.0 and analyzed with a paired t-test. The muscular activities of the TRA, VM, and VL significantly increased (P<0.05), while the activity of the ES significantly decreased (P<0.05) during stair ascent when the ADIM was maintained than when it was not. In conclusion, the stair ascent with ADIM maintained activated the abdominal muscles to control trunk balance and perform lumbar stability, simultaneously reducing excessive lumbar lordosis or pelvic anterior tilt which will help to improve the function of the musculoskeletal system.