The paper presents a mechatronic system used to study the human gait and the running step. The device consists of a pressure sensor-electronic device assembly which aquires data collected while walking or running, emphasizing the three phases of the running step. Using the data gathered using this device, it is possible to assess the energetic and control parameters and to evaluate athlete’s performance. This device can also be used in highlighting the deficiencies during gait or running, pointing the lack of synchronization between left and right lower limb during the running, the power differences between them, the pressure difference on the ground, the imbalances between the force and speed in training and beyond. All these considerations are based on the study of essential stage in running represented by the impulse action of the foot on the ground.  The problem solved by the mechatronic system proposed consists of the fact that all the data are gathered on a memory card under real conditions, including the configuration of the land on which the run (or jump) is made, the environmental factors (temperature, wind) influences.