According to leading international orthopaedic specialists, some 80% of all back problems are caused by weak back muscles or to be more precise weak lumbar extensors. The University of Florida was responsible for the pioneering research into the muscular causes of back problems. It was the first to conduct comprehensive research into the theory that weak back muscles could be a cause of chronic low back pain.
This research only became possible after the invention of a lumbar extension machine by Arthur Jones. Strength tests conducted on the lower back muscles of several thousand individuals produced some surprising results. The majority—who included highly trained athletes—had weak lumbar extensors.