Power hitting : finding the right implement

Abstract

Striking a ball with an implement occurs often in sports. Athletes are given a large variety of options to choose from when they select their implements. The motivation for this study was the need for a simple method that athletes can use to choose the implement that will allow them to perform their best. The specific focus of this work is identifying the weight properties an implement should have in order to have the most "powerful" shot. The "power" of a shot is measured by how fast the athlete is able to make the ball move after hitting it (the outgoing ball speed). The particular weight property of interest is the implement's mass moment of inertia about an axis through its handle. Five simple models for how the implement's moment of inertia affect the outgoing ball speed are developed and compared, primarily in a field hockey case study. A new model based on the physiology of muscles proves to be more successful in capturing the behavior observed in real striking of sports balls and is the primary contribution of this study. Overall, the models predict that heavier implements than are currently used would produce more powerful shots. This result is reasonable, as implement's are rarely selected with the sole purpose of hitting power shots. Additional objectives should be incorporated into the model to more broadly aid in an athlete's implement selection process.