An impact detection device, as well as a system that includes such a device for simulation of a combat sport, or more generally for use in a sport in which the user creates an impact by striking an adversary or an object. This device includes a sensor that detects an impact and its intensity, which is mounted on a printed circuit, together with an indicator that activates when the detector detects an impact and/or in order to indicate to a user that the user must generate an impact. The indicator is imbedded in a protective covering so that it is located near the surface of its embedding material. The indicating means are mounted directly on the printed circuit, so that the embedding material also covers the printed circuit and the sensor.