Abstract: A deep water exercise belt, which supports the user in deep water in an upright, running position so as to allow vigorous exercise without placing body weight on the legs, involves a waist encircling belt of flexible buoyant material of uniform thickness which is shaped to provide greater flotation at the back of the user. Shaping includes an increased width of the belt on the back while forming the bottom of the belt to avoid hip motion of the user. The belt may be constructed of a chemically cross-linked polyethylene having an extremely fine closed-cell structure. The interior surface of the belt is smoothed so as to provide a suction effect against the body, while the exterior surface may be roughly textured to provide additional resistance to movement through water. A separate band of elasticized material is intertwined through the buoyant belt so as to buckle at the front of the user and hold the exercise belt in close contact with the waist.