The invention relates to a method for operating a brake system of a motor vehicle with at least one front axle and one rear axle, and to a brake system using the method. The brake system comprises: a brake booster with a brake input element which is to be operated by a driver of the motor vehicle and is coupled to an actuation position sensor for providing a signal corresponding to a driver braking request; a brake master cylinder coupled to the brake booster and in turn coupled to a brake medium reservoir; fluid lines which are in fluidic communication with the brake master cylinder and the brake medium reservoir, and are also in fluidic communication with braking devices on wheels of the axles via an arrangement of valves, wherein the wheels are each also coupled to generators producing braking torque in addition to the braking devices. The method comprises the following steps: generating a hydraulic idle travel by means of the arrangement of valves and a corresponding triggering of the valves by means of a control unit coupled to the valves, wherein a hydraulic pressure build-up for decelerating a wheel speed of the respective wheels is prevented by generating the idle travel during actuation of the brake input element by the driver; and producing a generator-produced braking torque at each of the wheels for decelerating the wheel speed of the respective wheel, on the basis of the driver's braking request.