An inflatable structure for physical exercise in water, said inflatable structure being able to be associated to a support wall for said inflatable structure, the support wall extending along a plane substantially orthogonal to a reference plane substantially corresponding to a stretch of water, the inflatable structure comprising: - at least one first main surface facing the support wall, said at least one first main surface extending on a plane substantially orthogonal to the reference plane; - at least one second main surface opposite said at least one first main surface; - at least one first connecting side surface between the at least one first main surface and the at least one second main surface and at least one second connecting side surface, opposite said at least one first connecting side surface, between the at least one first main surface and the at least one second main surface, - at least one upper connecting surface between the at least one first main surface and the at least one second main surface, said at least one upper connecting surface being located in the upper part of the inflatable structure; - at least one lower connecting surface, opposite said at least one upper connecting surface, between the at least one first main surface and the at least one second main surface, said at least one lower connecting surface being in the lower part of the inflatable structure, a lower portion of said at least one first main surface, the at least one lower connecting surface, and a lower portion of said at least one second main surface defining a lower portion of the inflatable structure, the inflatable structure being able to be associated to the support wall so that the lower portion of the inflatable structure is underneath the reference plane, wherein the inflatable structure comprises means for accessing the inflatable structure, which are configured to allow a person the access from the water to the inflatable structure, said access means being operatively connected to the lower portion of the inflatable structure, said access means extending along a plane substantially orthogonal to the reference plane. - at least one first main surface facing the support wall, said at least one first main surface extending on a plane substantially orthogonal to the reference plane; - at least one second main surface opposite said at least one first main surface; - at least one first connecting side surface between the at least one first main surface and the at least one second main surface and at least one second connecting side surface, opposite said at least one first connecting side surface, between the at least one first main surface and the at least one second main surface, - at least one upper connecting surface between the at least one first main surface and the at least one second main surface, said at least one upper connecting surface being located in the upper part of the inflatable structure; - at least one lower connecting surface, opposite said at least one upper connecting surface, between the at least one first main surface and the at least one second main surface, said at least one lower connecting surface being in the lower part of the inflatable structure,