Conclusions
The results of this study indicate higher maximal amplitude of normalized electrical activity of the IES, CES in patients with chronic LBP compared to those without LBP. The normalized electrical activity of the GM and HAM, although not statistically significant, was also greater in women with LBP than healthy subjects. These findings demonstrate an altered activity pattern of the lumbo-pelvic muscles during hip extension in patients with chronic LBP. This information is important for investigators using PHE as either an evaluation tool or a rehabilitation exercise