Analysis of Sway in Ballroom Dancing and Other Sports

Abstract

The “Sway” is one of the important techniques in ballroom dancing and also is seen in many other sports such as skate, ski, running, and sports with vehicles etc. According to the authorized syllabi of the ballroom dancing, the sway is defined as the inclination of the body away from the moving foot and towards the inside of the turn. However, there are some questions to this definition of sway. which is cleared in the present analysis and a more precise classification is given with mechanical analysis introducing a new concept of inclination and bending. First, basic mechanism of the sway is explained as the balance of the inertia force of the dancer's body and the force exerted by the inclination of the body using an inclined one bar element model. Mathematical functions are introduced to simulate the translational body movement and the amount of inclination in the sway is estimated by the analytical solution. Further a two-element model is introduced in the present analysis which includes both the inclination and the bending effects. This model explains the control and stability of the sway and to match the function of the force to explain the swing movement and the function of force by the sway analysis. The sway process is classified in the three stages, and the change of the inclination and bending angles with time is demonstrated for each stage with taking examples for some figures.