An intervention to prevent chronic back pain and muscular-skeletal disorder (MSD) was implemented in the second half of 2003 at an automobile factory targeting employees from the cable construction division who were redeployed internally to a another division of the plant. This action-research consisted of exploring the benefits of establishing specialized gym classes for back exercises and re-education at the workplace to help prevent chronic lower back pain. Employees who had previously reported lower back pain that was either slightly disabling to none incapacitating and those who were in-line to be redeployed to another division were all offered the opportunity to undertake a medical exam and physical therapy check-up and to respond to a self-administered questionnaire in order to assess the functional state of of each employee, his perception of pain, and the manifestation and impact of this in daily life. Employees were oriented to appropriate gym and physical therapy classes for re-educating and improving back strength under the supervision of a physical therapist. As a follow-up to this, in between sessions, the workers were invited to redo the assessment tests in order to assess and appraise the value of the effects of the exercises. The action-research carried out in the workplace shows a positive contribution of the gym classes specialized for back exercises and re-education training to the improvement of the status of those persons suffering from lower back pain. In addition, placing employees in new professional positions following their completion of these gym and physicals therapy sessions proves to be essential for validating the acquisition of knowledge gained and the commitment to adjusting to the job position.