Abstract: A device in particular for use in the field of sport practice and body-building, for a person's muscular exercise. The device enables the development of quadriceps and of the gluteal muscles and comprises a support surface for the feet and elements for applying a force of resistance to the movements of the person's legs to shift from a bent position to an extending position by unfolding the knees. The force applying elements comprise a harness pressing on the upper side of the thighs. The invention is applicable to the manufacture of body-building machine.

Abstract: The invention concerns a device in particular for use in the field of sport practice and body-building, for a person's muscular exercise. Said device enables the development of quadriceps and of the gluteal muscles and comprises a support surface for the feet and means for applying a force of resistance to the movements of the person's legs to shift from a bent position to an extending position by unfolding the knees. The invention is characterised in that the force applying means comprise a harness pressing on the upper side of the thighs. The invention is applicable to the manufacture of body-building machine.

Abstract: Non-circular front chain wheel for a crank gear is comprised of a crank gear wheel allowing to a progressive increase of the cycling torque from the dead point up to the point where the extension of the leg allows to create the maximum effort, due to a progressive variation of the primitive radius of the toothing between these two points, followed by a rapid decrease to the next dead point. The principle is that the force to be provided is proportional to the muscular force that the user may provide. The non-circular front chain wheel essentially pertains to the cycle industry but may also find applications in other fields, for example physical exercisers for body building or reeducation, and in general all apparatus utilizing cycling motion and a chain or belt transmission system between the front wheel or wheels of the crank gear and one or a plurality of pinions actuating the device to be driven.