Abstract: An apparatus for teaching an individual proper body rotation when striking a ball is disclosed which includes an elongated body member having a first end portion, a medial portion and a second end portion. A strap is connected to the elongated body member for securing the elongated body member in a is substantially horizontally disposed position on a portion of a lower lumbar region of the individual's back whereby at least a portion of the medial portion and the second end portion of the elongated body member extends outwardly from the individual. Upon the individual assuming a ball striking position and simulating a swing or a ball striking motion, at least the second end portion of the elongated body member is caused to cross over a ball striking zone when the individual's hips, lower body and upper body are properly rotated during the swing or ball striking motion. The apparatus may further include a back rest assembly, a rib assembly and a propiteal fossa engaging assembly.