A control device for an electrical stimulation apparatus in the present disclosure includes a control section that adjusts an output of an electrode. The electrode gives electrical stimulation to a predetermined part of a body doing a pedaling exercise. The predetermined part is at least one of a leg and an arm. The control section adjusts the output of the electrode in such a way that the electrical stimulation is given to the predetermined part in relation to an exercise unit of the pedaling exercise. Furthermore, the control section adjusts strength of the electrical stimulation related to the exercise unit, in accordance with an amount of a physical activity of the body during the pedaling exercise. In this way, electrical stimulation can be given to a predetermined part in a variable manner during the pedaling exercise.