Electromyographic Comparison of Internal and External Obliques Using a Modified Version of Kendall\u27s Strength Test Positions for Upper and Lower Abdominals

The purpose of this study was to examine the activity of the internal obliques (upper abdominals) versus the external obliques (lower abdominals) during a modified version of Kendall\u27s upper and lower abdominal strength tests using surface electromyography on adults. The study was not correlated to Kendall\u27s theory due to the necessity to have the internal oblique electrode placed on the anterior abdomen. Twenty-four women and sixteen men participated in the study. All subjects were taught two positions ( easy and hard ) for both abdominal tests and performed eight trials. A normalized ratio was generated by dividing one hard trial by the mean of three easy trials for each position. A t-test revealed no significant difference between the activity of the external and internal oblique muscles in the two modified tests. There were no direct conclusions made regarding Kendall\u27s abdominal tests. In conclusion, further research is needed with appropriate electrode placement on the lateral abdomen to examine muscle activity in KendalI\u27s test positions for the upper and lower abdominals