The purpose of this investigation was to quantify the differences between one- and two-foot vertical jumping performances. Fourteen subjects performed both jump styles with a four-step, self-paced approach. While overall jump and reach heights were similar between one-foot and two-foot jumps, the strategies employed to achieve these results were notably different. One-foot jumps benefited from an increased takeoff height that was largely attributable to the elevation of the free swinging leg. Further, it was suggested that the actions of this limb may have helped slow the rate of extension of the support leg during the propulsion phase. Greater flight heights were achieved during two-foot jumps, as expected, but the magnitude of this difference was only about 9 cm. It was suggested that factors associated with the development of muscular tension, vertical velocity at touchdown, and horizontal approach speed may have all contributed to the unexpectedly small differences in flight height between one-foot and two-foot jumping performances.
The authors are with the Exercise and Sport Research Institute, Arizona State University, Tempe,AZ 85287-0404.