The Effect of Eight Weeks of Aquatic Walking Training on Kinematics and Hip-Trunk ‎Coordination during Walking in People with Chronic Back Pain

Low Back pain is one of the most common disorders that affect people's functional ability in daily life and workplace activities, as well as their general health and quality of life This study aims to investigate the effect of eight weeks of water walking training on kinematics and trunk-pelvic coordination during walking in people with chronic back pain.In this semi-experimental with pre-post test research design, 50 subjects with chronic back pain were divided into two control (25 subjects) and experimental groups (25 subjects) based on their weight and VAS pain index, so there are no any significant differences between weight and pain. The Mean±SD of height, weight and age in the control group were 170.62±6.8, 81±6.63 and 44.74±5.92, and in the experimental group were 167.16±7.62, 78.32±8.01 and 43.66±5.32 respectively. Noraxon IMU system was used to measure the pelvis and trunk kinematic variables during walking. After that, the angular information of the pelvis and trunk was extracted and after processing the range of motion variables, coordination with continuous relative phase index and variability of coordination were calculated. After the pre-test, the subjects were exposed to eight weeks of water walking training with a frequency of three days a week, and after the training, the pelvic trunk kinematic test was taken. The control group continued their daily activities after the pre-test. For statistical analysis, the repeated measure ANOVA was used for comparison (P≤0.05).The results of this study showed that training in water within and between groups reduces the range of motion of the trunk (P=0.001). On the other hand, the results of this study showed that training in water increases the coordination between the trunk and pelvis, which indicates greater coordination between the trunk and pelvis during walking (P=0.001). Also, the results showed that the variability of coordination after training in water decreases significantly within and between groups (P=0.001).The results of this study showed that performing six weeks of water walking training at different speeds due to the features of water training such as buoyancy and flow resistance reduces the range of motion of the trunk, and this decrease in range of motion balances the movement of the trunk concerning the pelvis, and the coordination between these two segments is increased. On the other hand, the results of this study pointed to the greater stability of walking of patients with back pain after performing the exercise, which indicates that the walking pattern in high repetitions is closer to normal walking.