An electromyographical comparison of trunk muscle activity during isometric trunk and dynamic strengthening exercises

Comfort, P; Pearson, S; Mather, D

Abstract

The purpose of this study was to compare rectus abdominis and erector spinae muscle activity during isometric (prone bridge [PB] and superman [SM]) and dynamic strengthening exercises (back squat, front squat [FS], and military
press). Participants (n = 10, age 21.8 6 2.6 years; body mass 82.65 6 10.80 kg, 174.56 7.2 cm), performed each exercise in a randomized order, using a repeated-measures design. Electromyographical (EMG) activity (sampling at 2,000 Hz) of the rectus abdominis (RA) and the erector spinae (ES) muscles was recorded throughout the duration of the exercises. Intraclass correlations demonstrated the highest levels of reliability for muscle activity during the isometric exercises; however, all exercises demonstrated high level of reliability (r = 0.764–
0.998, p # 0.01). The PB demonstrated significantly greater (p ,0.01) RA activity compared to all other exercises. The ES activity was significantly (p, 0.01) greater during the FS (1.01060.308 root mean square value [RMS (V)]) and SM (0.951 6 0.217 RMS[V]) and compared to all other exercises, although there was no significant difference (p . 0.05) between the FS and the SM exercise. The PB may be the most suitable exercise for strengthening the RA, compared to dynamic exercises at a low to moderate load, because of a higher level of muscle activity. The FS may be a useful alternative to isometric exercises when strengthening the ES, because it results in slightly higher muscle
activity levels when using only a light to moderate load. Because of the dynamic nature of the FS, this may also be more beneficial in transferring to activities of daily living and sporting environments.

Citation

Comfort, P., Pearson, S., & Mather, D. (2011). An electromyographical comparison of trunk muscle activity during isometric trunk and dynamic strengthening exercises. Journal of Strength and Conditioning Research, 25(1), 149-154. https://doi.org/10.1519/JSC.0b013e3181fb412f

• Journal Article Type: Article
• Publication Date: Jan 1, 2011
• Deposit Date: Jun 1, 2011
• Journal: Journal of Strength and Conditioning Research
• Print ISSN: 1064-8011
• Publisher: Lippincott, Williams & Wilkins
• Peer Reviewed: Peer Reviewed
• Volume: 25
• Issue: 1
• Pages: 149-154
• DOI: https://doi.org/10.1519/JSC.0b013e3181fb412f
• Keywords: electromyography, rectus abdominis, erector spinae, trunk strengthening
• Publisher URL: http://dx.doi.org/10.1519/JSC.0b013e3181fb412f
• Related Public URLs: http://journals.lww.com/nsca-jscr/pages/default.aspx