Women with CLBP had greater activity in the posterior oblique sling muscles than did women without CLBP during PHE. These findings suggest that an alteration can be made in posterior oblique sling muscle activities during PHE in women with CLBP.

No abstract

To investigate the selective activation of the infraspinatus muscle while minimizing the use of the posterior deltoid muscles during common shoulder external rotation exercises. [Subjects] Thirty-two ablebodied volunteers (18 males, 14 females; aged 22 to 31 years, mean ± SD, 24.7 ± 3.3 years) were recruited for this study. [Methods] The participants were instructed to perform four exercises: side-lying external rotation; prone abduction with external rotation; sitting external rotation, and sitting with abduction and external rotation exercise. The EMG signal amplitude was measured during each exercise. Surface EMG signals were recorded from the infraspinatus and posterior deltoid muscles. Differences among the exercises were tested using one-way repeatedmeasures analysis of variance. [Results] EMG activities of the infraspinatus and posterior deltoid muscles in prone abduction with external rotation were significantly higher than in the other exercises. The EMG ratio (infraspinatus/ posterior deltoid) was significantly higher in sitting external rotation than in the other exercises. [Conclusion] Based on these findings, sitting with external rotation should be used to minimize posterior deltoid activation and selectively stimulate infraspinatus muscle activity during shoulder external rotation exercise.

[Purpose] The aim of this study was to compare muscle activity of the posterior oblique sling during prone hip extension (PHE) on the floor and on a round foam roll. [Subjects] Twenty-two (11 male, 11 female) healthy volunteers were recruited for this study. [Methods] The participants performed PHE on the floor and on a round foam roll. Surface electromyography (EMG) was recorded from the contralateral latissimus dorsi (LD), contralateral erector spinae (ES), ipsilateral ES, ipsilateral gluteus maximus (GM), and ipsilateral biceps femoris (IBF). A paired t-test was used to compare muscle activity under the floor and round foam roll conditions. [Results] EMG activity of the contralateral LD, ipsilateral ES, and ipsilateral GM was significantly greater when PHE was performed on the round foam roll than on the floor. [Conclusion] Performing PHE on the round foam roll induced greater posterior oblique sling EMG activity than did exercise on the floor. These results suggest that the activation pattern of the posterior oblique sling during PHE is differs according to the type of surface (stable vs. unstable) on which it is performed.

Based on these findings, a stick exercise was an effective method to prevent excessive lumbar flexion and more helpful in developing hip flexion during a forward-bending exercise. These findings will be useful for clinicians to teach self-exercise during forward bending in patients with lumbar flexion syndrome.