Dynamic Evaluation of the Contractile Function of Lumbodorsal Muscles During the Locust Pose in Yoga by Real-Time Ultrasound

Abstract Background and Purpose: The purpose was to observe the changes in the thickness of lumbodorsal muscles that occur during the locust pose in yoga and how these changes occur. From the changes in muscle thickness that occur in the locust pose, the contractile function of lumbodorsal muscles can be evaluated.Methods: The changes in the thickness of the lumbodorsal muscles in the relaxed and contracted states were dynamically observed by real-time ultrasound when subjects were performing the locust yoga pose. Then, the thicknesses of the muscles during the two states were measured to calculate the ratio of contraction of each muscle and determine the statistical significance of the change in thickness of each muscle.Results: The mean thicknesses of the lumbodorsal muscles, including the multifidus, longissimus, iliocostalis, and quadratus lumborum, obviously differed between the relaxed and contracted states (P<0.005). The the mean C/R of the longissimus was 1.39±0.14 on the left and 1.40±0.16 on the right. The multifidus and iliocostalis had the second highest C/R. The mean C/R of the multifidus was 1.23±0.12 on the left and 1.24±0.15 on the right, and the mean C/R of the iliocostalis was 1.25±0.12 on the left and 1.24±0.14 on the right. The quadratus lumborum had the lowest C/R, and the mean C/R of the quadratus lumborum was 1.17±0.10 on the left and 1.19±0.11 on the right. Conclusions: The contractile activity of the lumbar muscles can be observed by ultrasound to evaluate the contractile function of the lumbar muscles.