# Vertical Jump Essay

604 Words3 Pages
KIN 335 - BIOMECHANICS LAB: Measurements of Vertical Jumping Performance Introduction: In a maximal effort vertical jump performance, the goal of the task is simply to jump and reach as high as possible. In many sports, the height to which an athlete can jump and reach is often of critical importance. In the absence of air resistance and other external forces, the upward projection of the whole body center of mass (CM) is completely determined by the vertical velocity at the instant of takeoff and the acceleration due to gravity. However, this quantity does not completely describe the overall jump and reach height that is observed. Purpose: The purpose of this laboratory is to measure and compare vertical jumping performance using three different methods. The Deterministic Factors of Vertical Jumping: The block diagram in Figure 1 is called a deterministic model. It provides an objective basis by which all important aspects of an athletic performance can be subjectively evaluated. The factors (blocks) of the deterministic model serve to describe the mechanical or mathematical relationships that govern vertical jump and reach performances. From Figure 1, it can be seen that the actual vertical height to which an athlete can jump and reach may be described by the sum of four lesser heights: takeoff height, flight height, reach height, and loss height (see Equation 1 and Figure 1). Jump and reach height = Takeoff Height + Flight Height + Reach Height – Loss Height (1) Jump and reach height may be considered to be the actual vertical height at which the athlete contacts the ball during a volleyball attack, releases a ball during a basketball lay-up, or touches the slats of a vertical jump testing device. Takeoff height defines the height of the athlete's center of mass (CM) at the instant the athlete leaves the ground. Flight height refers to the actual height to