Abstract
PURPOSE: The aim of this study was to assess the effects of diaphragm training on low back pain and thickness of stabilizer muscles of the lumbar spine. PATIENTS AND METHODS: Fifty-two individuals were recruited with a history of chronic low back pain in our randomized controlled trial. The participants were divided randomly into two groups. One of the groups took part in a complex training program and completed with diaphragm training (DT group, n=26). The control (C) group took part only in the complex training (n=21). The thickness of transversus abdominis, diaphragm, and lumbar multifidus muscle was measured with ultrasonography in two positions: lying and sitting. All muscles were assessed in relaxed and in contracted state in the lying position and in a relatively relaxed (calm sitting) and relatively contracted state (during weightlifting) in the sitting position. RESULTS: After the training, severity of the pain was significantly reduced in both the groups. Regarding the thickness of the muscles, there were no changes in group C. The thickness of transversus abdominis increased significantly in relaxed and in relatively relaxed state, but there were no changes in contracted and relatively contracted state in group DT. As for the diaphragm muscle, there were significant increase in the state of supine position and in relatively contracted state, but there was no notable change in relatively relaxed state. With regard to the thickness of lumbar multifidus, a significant increase was only found in the left-sided muscle in relaxed, relatively relaxed, and relatively contracted state and in case of the right-sided one in relatively contracted state in group DT. CONCLUSION: Our results suggest that diaphragm training has an effect also on the thickness of other active stabilizers of the lumbar spine, such as transversus abdominis and lumbar multifidus muscles.