This study examined whether there is an association between the presence of lumbar intervertebral disc degeneration (LDD) and the size and symmetry of the cross-sectional areas (CSAs) of the trunk muscles in combat sports athletes. Participants in this study were collegiate combat sports athletes. All intervertebral discs from L1/2 to L5/S1 in all athletes were assessed using MRI and a comprehensive grading system of LDD (grades I-V). All 151 athletes were divided into 2 groups: LDD and non-LDD. CSAs of trunk muscles at the L3/4 disc level were measured on MRI.