플랭크 운동 동안 엉덩관절 모음 · 벌림 저항이 몸통 근활성도에 미치는 영향 = Effects of Hip Adduction and Abduction Resistance During Plank Exercise on Trunk Muscle Activation

다국어 초록 (Multilingual Abstract)

Purpose: This study examined the effects of the isometric hip resistance directions on the trunk muscle activity during plank exercises in healthy adult males.
Methods: Thirty healthy men in their thirties with no history of low back pain or musculoskeletal disorders participated in this repeated-measures experimental study. Each participant performed the plank exercises under three conditions: neutral position, plank with isometric hip adduction, and plank with isometric hip abduction. Each condition was maintained for five seconds and repeated three times, with sufficient rest intervals between conditions to minimize muscle fatigue. The trunk muscle activity was measured using a wireless surface electromyography system. Electromyographic signals were collected from the erector spinae, rectus abdominis, external oblique abdominis, and internal oblique abdominis muscles and normalized to the percentage of the maximal voluntary isometric contraction (%MVIC). The collected data were analyzed using repeated-measures analysis of variance.
Results: The erector spinae muscle activity was significantly lower during the plank exercise with isometric hip abduction compared to the neutral and hip adduction conditions (p<.05). In contrast, the activities of the rectus abdominis, external oblique abdominis, and internal oblique abdominis were significantly higher during plank exercise with isometric hip abduction than during the neutral position (p<.05). In addition, isometric hip adduction during the plank exercise increased the abdominal muscle activity significantly compared to the neutral condition (p<.05).
Conclusion: These findings suggest that the direction of isometric hip resistance during the plank exercise significantly influences the trunk muscle activation patterns. In particular, plank exercise combined with isometric hip abduction may be an effective trunk-stabilization exercise by enhancing the selective activation of the abdominal muscles while reducing the excessive activation of the erector spinae. These results provide clinically useful evidence for designing trunk stabilization and rehabilitation exercise programs.