An interchangeable exercise arm assembly, comprising: (a) a quick release mechanism for an exercise arm assembly; (b) an exercise arm comprising a flexible exercise strap with a plurality of rings (32A, 32B) distally spaced apart from one another; wherein the quick release mechanism comprises: an elongated body with an aperture; a button assembly positioned near the distal end of the elongated body, the button assembly comprising a finger contact pad projecting upwardly out of the elongated body and a forwardly extending portion disposed within the elongated body, wherein the forwardly extending portion of the button assembly is moveable to: project into the aperture when the button assembly is in a locked position, or project away from the aperture when the button assembly is in an unlocked position; and a biasing member that urges the extending portion of the button assembly into the locked position, wherein the aperture is a curved aperture passing laterally across a distal end of the cylindrical elongated body, the curved aperture cutting downwardly through the cylindrical elongated body with a front end of the aperture being angled towards the distal end of the cylindrical elongated body, thereby forming a laterally extending front end of the aperture laterally extending across the cylindrical elongated body, characterised in that the elongated body is cylindrical the plurality of rings are square or triangular-shaped rings (32A, 32B); and in that the curved aperture is dimensioned to receive a laterally extending straight part of one of the plurality of square or triangular-shaped rings (32A, 32B) passing therethrough; and, when the forwardly extending portion of the button assembly is in the locked position, the ring (32A, 32B) is locked into position against the laterally extending front end of the aperture by the forwardly extending portion of the button assembly. (a) a quick release mechanism for an exercise arm assembly; (b) an exercise arm comprising a flexible exercise strap with a plurality of rings (32A, 32B) distally spaced apart from one another; wherein the quick release mechanism comprises: an elongated body with an aperture; a button assembly positioned near the distal end of the elongated body, the button assembly comprising a finger contact pad projecting upwardly out of the elongated body and a forwardly extending portion disposed within the elongated body, wherein the forwardly extending portion of the button assembly is moveable to: project into the aperture when the button assembly is in a locked position, or project away from the aperture when the button assembly is in an unlocked position; and a biasing member that urges the extending portion of the button assembly into the locked position, wherein the aperture is a curved aperture passing laterally across a distal end of the cylindrical elongated body, the curved aperture cutting downwardly through the cylindrical elongated body with a front end of the aperture being angled towards the distal end of the cylindrical elongated body, thereby forming a laterally extending front end of the aperture laterally extending across the cylindrical elongated body, characterised in that an elongated body with an aperture; a button assembly positioned near the distal end of the elongated body, the button assembly comprising a finger contact pad projecting upwardly out of the elongated body and a forwardly extending portion disposed within the elongated body, wherein the forwardly extending portion of the button assembly is moveable to: project into the aperture when the button assembly is in a locked position, or project away from the aperture when the button assembly is in an unlocked position; and project into the aperture when the button assembly is in a locked position, or project away from the aperture when the button assembly is in an unlocked position; and a biasing member that urges the extending portion of the button assembly into the locked position, wherein the aperture is a curved aperture passing laterally across a distal end of the cylindrical elongated body, the curved aperture cutting downwardly through the cylindrical elongated body with a front end of the aperture being angled towards the distal end of the cylindrical elongated body, thereby forming a laterally extending front end of the aperture laterally extending across the cylindrical elongated body, characterised in that the elongated body is cylindrical the plurality of rings are square or triangular-shaped rings (32A, 32B); and in that the curved aperture is dimensioned to receive a laterally extending straight part of one of the plurality of square or triangular-shaped rings (32A, 32B) passing therethrough;