Magnetic resonance imaging (MRI) was performed on 35 young competitive gymnasts and 10 control subjects in order to detect the number of degenerated discs and other lumbar spinal disorders. Lumbar radiographs were obtained from all gymnasts who showed evidence of disc abnormality on MRI. Eleven gymnasts had suffered from episodes of low back pain during exercises and eight were found to have evidence of back trauma. Only 3 of the 35 gymnasts had MRI evidence of degenerated discs associated with Scheuermann's manifestations and spondylolysis. Lumbar radiographs confirmed the diagnosis in these three cases. The results indicate that despite the excessive range of motion and strong axial loading of the lumbar spine that are associated with gymnastic maneuvers, incurable primary damage to the intervertebral discs is uncommon in young gymnasts during growth.