A device for stationary swimming in an above-ground or self-supporting swimming pool includes an item of equipment intended to surround the body of a swimmer, a flexible tether fastened at one end to the item of equipment, and at least one attachment pole with at least one hitching point for fastening to the other end of the tether. The base of the attachment pole is removable manner and has at least one anchoring plate extending laterally with respect to the base of the pole. The plate has an elongate shape and a size such that a large portion of its length can be slipped beneath one of the ends of a water basin lying on the ground. The mass of water contained in the basin firmly blocks the pole, thereby immobilizing and stabilizing the attachment pole.