- 著者
- Tomoki Oshikawa Yasuhiro Morimoto Koji Kaneoka
- 出版者
- The Society of Physical Therapy Science
- 雑誌
- Journal of Physical Therapy Science (ISSN:09155287)
- 巻号頁・発行日
- vol.30, no.3, pp.434-438, 2018 (Released:2018-03-02)
- 参考文献数
- 13
- 被引用文献数
- 7
[Purpose] To compare the lumbar lordosis angle and electromyographic activities of the trunk and lower-limb muscles in the hip neutral position and external rotation during back squats. [Subjects and Methods] Ten healthy males without severe low back pain or lower-limb injury participated in this study. The lumbar lordosis angle and electromyographic activities were measured using three-dimensional motion-capture systems and surface electrodes during four back squats: parallel back squats in the hip neutral position and external rotation and full back squats in the hip neutral position and external rotation. A paired t-test was used to compare parallel and full back squats measurements in the hip neutral position and external rotation, respectively. [Results] During parallel back squats, the average lumbar lordosis angle was significantly larger in hip external rotation than in the hip neutral position. During full back squats, lumbar erector spinae and multifidus activities were significantly lower in hip external rotation than in the hip neutral position, whereas gluteus maximus activity was significantly higher in hip external rotation than in the hip neutral position. [Conclusion] The back squat in hip external rotation induced improvement of lumbar kyphosis, an increasing of the gluteus maximus activity and a decrease of both lumbar erector spinae and multifidus activities.
- 著者
- Yasuhiro Morimoto Tomoki Oshikawa Atsushi Imai Yu Okubo Koji Kaneoka
- 出版者
- The Society of Physical Therapy Science
- 雑誌
- Journal of Physical Therapy Science (ISSN:09155287)
- 巻号頁・発行日
- vol.30, no.1, pp.154-158, 2018 (Released:2018-01-27)
- 参考文献数
- 14
- 被引用文献数
- 7
[Purpose] To measure electromyographic activity of the piriformis using fine-wire electrodes during 7 hip movements. [Subjects and Methods] Eleven healthy men, without severe low back pain or lower limb injury, participated in this study. Fine-wire electrodes were inserted into the piriformis and surface electrodes were attached to the muscles in the hip region and the trunk muscles on the dominant arm side. Electromyographic signal amplitude was measured during 7 hip movements: side-lying external rotation in hip neutral position, side-lying abduction in hip neutral position, side-lying abduction in hip external rotation, side-lying abduction in hip internal rotation, prone extension in hip neutral position, prone extension in hip external rotation, and prone extension in hip internal rotation. Repeated-measures one-way analysis of variance was used to examine electromyographic activity in each of the 7 hip movements. [Results] Piriformis electromyographic activity was highest during prone hip extension in external rotation. Both the superior and inferior portions of the gluteus maximus were also highly activated during prone hip extension in external rotation. [Conclusion] Prone hip extension in external rotation induced high electromyographic activity in the piriformis and superior and inferior gluteus maximus muscles.