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Muscle activity of the erector spinae during Pilates isometric exercises on and off Swiss Ball
1Federal University of Rio de Janeiro Rio de Janeiro, RJ, Brazil.
Background:
The purpose of this study was to investigate the muscle activity of the Erector spinae (ES) during Pilates isometric exercises on and off Swiss ball.
Methods:
Fifteen women (22.9±2.1years, 171.7±4.7 cm, 65.7±5.3 kg and 11.2±3.2% of body fat) with previous Pilates experience (1±0.9 years) participated as subjects in this study. In the first test session, the anthropometric data and maximal voluntary contraction (MVC) was measured. In the second test session, three isometric exercises were conducted on and off the Swiss ball: back extension (BE), back extension with elbows flexed (BTF) and back extension with elbows extended (BTE). During all exercises, average integrated electromyography (IEMG) from ES muscle was collected and analyzed. A one-way ANOVA with repeated measures followed by Bonferroni post hoc was adopted to compare the muscle activity (P<0.05).
Results:
ES activity was higher for BT, BTF and BTE on stable surface than on Swiss ball, respectively. Significant differences were observed for the ES activity during BTE exercise when compared to BTF and BT on and off Swiss ball, respectively.
Conclusion:
The Swiss ball may not provide a potential effect on ES activity during Pilates isometric exercises with similar posture when compared to stable surfaces. Therefore, the combination of BT, BTF and BTE exercises may be an interesting alternative to provide progressive increases in the ES activity.
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