To our knowledge, there has been not enough studies that investigated the effect of core strengthening by functional exercise on pain, functional disability and core muscle strength in patients with chronic mechanical low back pain. Therefore, this study may open up ways to other researchers to investigate and build up on this effect if present and address such an important issue.~the finding of this proposed work may help patients with chronic mechanical low back pain by addressing their pain, functional limitation, and/or participation restrictions. Consequently, this can speed up their recovery, return to work, decrease cost of treatment, improve psychological status, decrease level of irritability, and improve overall quality of life.~Patients with chronic mechanical low back pain will be recruited after approval of ethical committee of the faculty of physical therapy, Cairo University. All participants will sign a written informed consent form.~The subjects will be randomly assigned into one of two groups:~Group I (control) will receive advices only.~Group II (experimental) will receive a suggested functional exercise program plus advises.~the measurments will take before and after treatment programe .
The aim of this study will be to investigate the effect of functional exercise on pain, functional disability and core strength in patients with chronic mechanical low back pain .