A Study of the Effects of Elastic Ligaments on the Outside Pass in Soccer

Abstract

It is generally accepted that ligaments play a role to stabilize the joints by holding the position of bones. We think it has a role not only for that but also for improving the performance of sports activities by thier elasticity: outside pass in soccer, bump in volleyball, and forehand in tennis. In these sports activities, the force from balls applies to the bones in the direction which dislocates the bones. The elastic ligaments are considered to deform or oscillate, and these seem to increase the velocity of the balls when they leave. The effect of elasticity of ligaments remains to be unclear. This study aims to show that the elasticity of ligaments effects on performance of sports. In one example of sport activities, the elasticity of them has effects on the outside pass in soccer. We formed the equation of motion of outside pass and obtained the velocity when the ball leaves from the legs. As a result, spring constant of the medial collateral ligament has affects on the velocity of balls more than that of lateral collateral ligament. This result suggests that the spring constant of them is one of the elements which determines the velocity of balls in outside pass in soccer.