1. A portable automatic system of acquisition and recording of information on the movement of one or more parts of the body of a monitored subject through a corresponding number of motion sensors placed on respective parts of the body, the movement of which must be detected and of assessment data on the global motion activity of the subject during an established interval of time, characterized by comprising one or more motion sensors respectively placed on parts of the body of a subject under observation; an analog-to-digital converter associated to each sensor converting an analog signal generated by the sensor into digital data; a logic block of calculation of predefined parameters from successive sequences of said digital data for each sensor; first fuzzy logic means processing said calculated parameters and generating corresponding fuzzy labels of classification of the movement detected by each of said sensors during the same established interval of time; a storage memory of said parameters and/or fuzzy labels; second fuzzy logic processing means of classification of the global motion activity of the subject under observation input with sets of fuzzy labels relative to the different motion sensors and outputting a representative index of the global motion activity of the subject in said interval.