Comparison of Eight Weeks Opened and Closed Chain Exercises on Strength and Range of Motion in Female with Chronic Non-specific Low Back Pain: A Pilot Study

 Low back pain is one of the most common musculoskeletal problems that comes with huge costs and has been reported as one of the main causes of disability. The purpose of this study was to compare eight weeks of opened and closed chain exercises on strength and range of motion of lower limb in female volleyball players with chronic nonspecific low back pain.

 The quasi-experimental research method with the pre-test and post-test was employed in the study. The study population consisted of all Between female volleyball players with nonspecific chronic back pain of Shiraz city, with an average age of 20 to 30 years, among whom 24 participants were selected by purposive sampling. After filling out the Quebec, diagnosis and confirmation of orthopedic physician, the participants were divided into 2 groups of 12 participants as intervention group 1 (opened chain exercises) and 12 participants as intervention group 2 (closed chain exercises). Participants strength was evaluated by employing Dynamometer and the range of motion by utilizing Modified Schober test as pre- and post-tests. The covariance test was utilized to analyze the data in SPSS-22.

 In the intervention group 1, the mean score (standard deviation) of the range of motion increased from 14.9 (1.4) in the pre-test to 16.1 (1.7) in the post-test, and in the intervention group 2, from 15 (1.1) in the pre-test to 17 (1.2) in the post-test (P<0.001), both training protocol increased range of motion. In the intervention group 1, the mean score (standard deviation) of strength increased from 63.3 (4.3) in the pre-test to 74.2 (4.2) in the post-test, and in the intervention group 2, from 64 (4.1) in the pre-test to 74.6 (4.1) in the post-test (P<0.001), both training protocol increased strength. And the results of analysis of covariance showed there was no difference between the exercise groups of open kinetic chain and closed kinetic chain in terms of range of motion and in terms of strength and by controlling the effect of the pre-test.

 The results revealed that the open and closed kinetic chain exercises of this study are effective in improving strength and range of motion by strengthening the muscles that are often associated with spine and pelvic control. More precisely, the results of the present study confirmed the effect of open and closed kinetic chain exercises on strength and range of motion in the participants, if none of the training methods was superior to the other.