Effect of Specific Postural and Breathing Instructions on the Sagittal Alignment of the Spinopelvic Complex Before and After a Dedicated Muscle Strengthening Program: A Pilot Study in a Gymnast Population.

Background: Gymnasts are reported as a population at high risk of low back pain. The prevention and treatment of low back pain often rely on improving the effectiveness of deep stabilizer muscles through exercises that aim to reach spinal alignment and axial lengthening. However, the scientific evidence regarding the effect of the specific instructions used during exercises on the spinopelvic complex is still lacking. To address this gap of knowledge, the aim of this pilot study was to examine the effect of specific postural and breathing instructions (spine straightening, forced expiration and perineal contraction) on the sagittal alignment of the spine before and after fifteen weeks of a specific muscle strengthening program. Methods: Low-dose biplanar radiographic images were taken in neutral position and in the five specific postures before and after the program and associated skeletal 3D reconstructions were performed allowing calculation of sacral slope, pelvic tilt, lumbar lordosis and thoracic kyphosis. Results: Sixteen gymnasts completed the entire protocol and were included in the analysis. At the end of the program, most of the postures tested led to a decrease in sacral slope, an increase in pelvic tilt, a reduction in lumbar lordosis, and a decrease in thoracic kyphosis, but with varying efficiency; the condition combining spine straightening, perineal contraction and forced expiration appeared to be the most effective in influencing all parameters simultaneously. Conclusions: The results strongly encourage combining an instruction of spine straightening with instructions of both expiration and perineal contraction, which is information of interest for coaches, physiotherapists and medical professionals.