Effect of Knee Extensor Training on the Lumbar Spine

Knee Extensor-Focused Biomechanical Intervention for Pain, Posture, and Disability in Non-Specific Low Back Pain: A Randomized Controlled Trial

The goal of this clinical trial is to learn if knee extensor training with different protocols works to treat LBP in adults.. The main questions it aims to answer are:

What are the comparative effects of open and closed kinetic chain knee extensor strengthening exercises versus lumbar stabilization exercises on lumbar curvature, postural control, and disability in individuals with non-specific low back pain? 1.4.2. How does open kinetic chain knee extensor strengthening affect pain, functional capacity, and lumbar spine stability compared to closed kinetic chain exercises in individuals with non-specific low back pain? 1.4.3 What is the effect of open kinetic chain knee extensor strengthening on pain, functional capacity, and lumbar spine stability compared to conventional lumbar muscle exercises in individuals with non-specific low back pain? 1.4.4 What is the effect of closed kinetic chain knee extensor strengthening on pain, functional capacity, and lumbar spine stability compared to conventional lumbar muscle exercises in individuals with non-specific low back pain? 1.4.5 What is the effect of open kinetic chain knee extensor strengthening on pain, functional capacity, and lumbar spine stability in individuals with non-specific low back pain? 1.4.6 What is the effect of close kinetic chain knee extensor strengthening on pain, functional capacity, and lumbar spine stability in individuals with non-specific low back pain? 1.4.7 What is the effect of conventional lumbar extensor strengthening on pain, functional capacity, and lumbar spine stability in individuals with non-specific low back pain Researchers will compare three different exercise protocols to a control group (will not receive exercise) to see if knee extensor training has an effect on problems associated with LBP.

Participants will:

• Exercise three times per week for 8 weeks
• Be assessed before, 4 weeks after, and 8 weeks after intervention

Inclusion Criteria:

I. Males aged 40 to 60 years, II. nonsmokers, III. with normal body mass index IV. of Saudi nationality, V. office workers, VI. suffering from chronic NLBP for 12 weeks or more with a moderate disability according to the Oswestry Disability Index (score of 21 - 40%) moderate activity level according to the Arabic version of the International Physical Activity Questionnaire short form .

Exclusion Criteria:

I. Previous spinal surgery, fracture, deformity, or disease. II. Neurological deficit and Lower limb deformity or fracture, or disease. III. Mental or psychological illness. The Arabic version of the Self-Reporting Questionnaire (SRQ-20) developed by the World Health Organization (WHO) to screen for common mental disorders such as depression and anxiety, uses a cut-off score to distinguish between individuals with and without significant psychological distress. A score of 7 or below is generally considered "normal", indicating no significant psychological distress (Al-Subaie et al., 1998).

IV. Systematic chronic illnesses such as hypertension, cardiac and respiratory disorders, and diabetes mellitus.