Horizontal jumping events in track and field include both the long and the triple jumps. Each event consists of an approach run followed by a take-off from a board (20 cm long and 1 m wide) located on a runway and landing into a sand-filled pit. Unlike long jumping, described in Chapter 20 by Scott, which involves one dynamic explosion at take-off, the triple jump sequence is comprised of (as the name implies) three separate take-offs. The hop phase (take-off and landing on the same foot), the step phase (take-off and landing on the opposite foot), and jump phase (takeoff from one foot to landing on both feet into a sandpit) comprise the ordered sequence of events following the approach run to the take-off board. The function of the approach run is to propel the jumper down the runway, at a high but controlled velocity, in preparation for the hop phase at take-off. Previous research has shown that the horizontal velocity attained in the approach run is a critical factor in the performance of jumps for distance and directly influences the distance that can be achieved (Hay, 1988; Hay and Koh, 1988; Miller and Hay, 1986).