This article aims to recommend easy, reproducible and valid physical tests and questionnaires to allow a functional and physical assessment of sub-acute and chronic low back pain patients. We recommend the pain visual analogue scale, the French translation of the Roland-Morris Disability Questionnaire (EIFEL) and the Dallas questionnaire to appreciate pain intensity and its influence on patients' quality of life. Sorensen's test is recommended in order to assess trunk extensor muscles endurance. We suggest to measure pelvic and lumbar flexion mobility by means of the inclinometer technique. The test described by McQuade is recommended to assess abdominal muscles static endurance.