Bilateral Activity of Spine Extensors and Rotators during Asymmetric Lumbar Stabilization Exercises Executed in Prone, Quadruped, and Standing-Prone Positions

(1) Background: Most daily activities and sport gestures involve asymmetric movement patterns of the upper and lower extremities, transferring asymmetric mechanical loadings to the spine. Therefore, asymmetric lumbar stabilization exercises are frequently prescribed in athletic programs and preventive/rehabilitation interventions. This study analyzed the bilateral activity of the thoracic erector spinae (ES), lumbar multifidus (MF), external oblique (EO), and internal oblique (IO) during asymmetric lumbar stabilization exercises executed in prone, quadruped, and standing-prone positions, rising an upper and/or lower limb in all possible combinations. A limited subset of these data has been previously published in earlier studies. (2) Methods: Surface EMG signals were bilaterally recorded from the selected muscles using wireless EMG sensors. (3) Results: ES, MF, and oblique muscles' activity was significantly higher in prone, standing-prone, and quadruped positions, respectively, and was maximized by specific limb rise combinations (up to 69%, 64%, 34%, and 24% maximum-voluntary-isometric-contraction for ES, MF, EO, and IO). The bilateral difference in muscle activation was significantly higher in the quadruped position and revealed different strategies used to stabilize the body in response to the different exercise conditions. (4) Conclusions: The study results can provide deeper insights into the stabilizing function of the lumbar and oblique muscles and aid in designing optimal progressions for lumbar stabilization exercises.