A Comparison of Flexi-bar and General Lumbar Stabilizing Exercise Effects on Muscle Activity and Fatigue

[Purpose] The objective of this study was to compare the effects of flexi-bar training and general lumbar stabilization training on muscle activity and fatigue. [Methods] Twenty normal persons participated in this study. After warm up and a Maximum Voluntary Isomeric Contraction (MVIC) test, participants performed bridging exercise, quadruped lumbar stabilization exercise on quadruped and curl-up, with and without the flexi-bar training, each exercise lasting for 30 seconds. Electromyography was used for the assessment of the muscle activity and fatigue of the rectus abdominis, erector spinae, external oblique and internal oblique muscles. [Results] The bridging and quadruped exercises with the flexi-bar elicited significant increases in the muscle activates of the muscle groups. The curl-up exercise with the flexi-bar showed significant differences in external oblique and internal oblique muscle activities compared to the exercise without the flexi-bar. Muscle fatigue showed different results depending on the exercise. [Conclusion] Generally, flexi-bar exercise induced greater muscle activation and fatigue. However, because there were differences of effect dependent on the posture, we should prescribe the appropriate exercise for the target muscles.