The Dynaback is used for strengthening the abdominal muscles, besides dynamically re-educating the spine. It is endowed with an innovative characteristic which originates from the likelihood of applying controlled elastic force in order to attain a steady rehabilitation. The product facilitates maximizing activation of slanting abdominal muscles, along with rectus abdominis. This is done without the unnecessary activation of rectus femoris and ileopsoas and concession of the rachis muscle. Besides being readily accessible, it optimizes postural comfort. Further, the exercises are carried out smoothly. The product has been made at par with the necessities of the Salvioli® technique. It is a medical instrument which is in conformity to the European Directive 93/42/EEC.