When a dancer is on balance, which is commonly referred to as being 'on center', they are in static equilibrium. This is achieved by the dancer's center of gravity being located directly over their contact point with the ground. If the dancer's center of gravity is not lined up with the contact point, they will experience an angular acceleration from the force of gravity. This happens because since both the normal force from the floor and the frictional force on the dancer are now at an angle to the vertical line connecting the contact point and the center of gravity so they exert a torque. This torque is what causes the angular acceleration of the body.         A larger contact area with the floor makes for easier balancing because the vertical line connecting the center of gravity and the contact point can reside above any point within the contact area. For example, if both feet are on the ground there is a large area that the center of gravity can be positioned on, but if only the tip of one foot is on the ground, this area is much smaller. Therefore, it is much more difficult and requires a lot more strength to dance en pointe.         Since the human body can never be truly still, the dancer must constantly be making small adjustments with their muscles in able to maintain a balance. By slightly adjusting specific muscle groups from the feet to the torso, and sometimes the position of the arms, a dancer can move their center of gravity in order to keep it as close as possible to being above their contact point with the floor.

Laws, K. (2002).