Abstract: A convertible side plank and balance exercise device includes a platform and a base extending rearwardly from the platform. The convertible exercise device has a circular or oval front perimeter that extends around the platform. The base has a domed rear surface. A front side of the device includes left and right footwells for receiving a left shoe and a right shoe when the device is in a side plank exercise configuration. The device further includes removable left and right footwell inserts that are removably insertable into the footwells to provide a flat front surface on the front side of the device in a balance exercise configuration. The base includes an air chamber with an inflation and deflation valve and a distensible rear panel comprising the domed rear surface, the rear panel collapsing for storage and shipping when the air chamber is deflated.

Abstract: A new method of performing a side plank exercise uses a side plank exercise device in the shape of a spherical cap or a cone. The side plank exercise device includes a front end that is circular or oval. The side plank exercise device also includes a rear end tapered from the front end. The rear end is a spherical cap. The front end has a flat or a cavitary surface. The front end also includes two recesses for receiving a left shoe and a right shoe. The two recesses are two inches deep and also uneven in depth. Each recess further incorporates a grip at its bottom. The grip includes protruding lines or spherical caps. The device further includes an edge at the front end that extends outwardly from the front end. The edge includes an attachment point with a crossbar and an attachment cavity receiving the crossbar.

Abstract: A new method of performing a side plank exercise uses a side plank exercise device in the shape of a spherical cap or a cone. The side plank exercise device includes a front end that is circular or oval. The side plank exercise device also includes a rear end tapered from the front end. The rear end is a spherical cap. The front end has a flat or a cavitary surface. The front end also includes two recesses for receiving a left shoe and a right shoe. The two recesses are two inches deep and also uneven in depth. Each recess further incorporates a grip at its bottom. The grip includes protruding lines or spherical caps. The device further includes an edge at the front end that extends outwardly from the front end. The edge includes an attachment point with a crossbar and an attachment cavity receiving the crossbar.

Abstract: A new side plank exercise device is in the shape of a spherical cap or a cone. The side plank exercise device includes a front end that is circular or oval. The side plank exercise device also includes a rear end tapered from the front end. The rear end is a spherical cap. The front end has a flat or a cavitary surface. The front end also includes two recesses for receiving a left shoe and a right shoe. The two recesses are two inches deep and also uneven in depth. Each recess further incorporates a grip at its bottom. The grip includes protruding lines or spherical caps. The device further includes an edge at the front end that extends outwardly from the front end. The edge includes an attachment point with a crossbar and an attachment cavity receiving the crossbar.