From: A protocol for clinical trial study of the effect of core stabilization exercises on spine kinematics during gait with and without load in patients with non-specific chronic low back pain
The age range of 18–45 years.
Current nonspecific Low back pain Lasting more than 12 weeks.
Sciatic nerve root involvement
Pain radiating to the leg below the knee
Paresthesia in the feet
Motor deficits in the lower extremity muscles
Acute spinal disc herniation
Previous surgery or fractures in lumbar spine or Other bonny structures
Recent any significant trauma to the musculoskeletal system such as bonny, muscular, ligamentous and soft tissue structures in the upper, lower extremity, head, neck and trunk that might interfere with gait [10, 16]
Any clinical conditions such as musculoskeletal, neurological, cardiac or pulmonary or symptom that might interfere with gait [10, 63]
Osteoarthritis of the knee and hip 
Recent unexplained weight loss
BMI above 30 kg/m2  (see the participants section)
Any medical condition which have contraindications to exercise therapy including acute (not reoccurring) low back injury occurring within the last 12 weeks, current tension sign, pregnancy, inflammatory disease, sever osteoporosis, arthritis and bone disease [37, 45, 64]