The back consists of the vertebrae between these bones, the spinal cord (which contains the nerves) and muscles, tendons and ligaments, the back and abdominal muscles. Help support the spine. The lower back (lumbar spine) supports most of the body's weight and helps with movement, twisting, and flexion. The most common low back injury is a strain in which the lower back muscles or tendons are stretched or torn. Tendons are tough bands that connect muscles and bones. Low back pain can be experienced by anyone. Athletes, especially soccer players and gymnasts Tends to be more stressed in training than during competition