## Weight balance movement

Every body has a center of mass; an imaginary point where gravity grabs a hold and pulls you down. Because the upper body is heavier than the legs, this point is located somewhat above the middle in a human being, in the underbelly between the tops of the hip bone crests. That is, if you're standing up straight. As soon as you bend over, extend an arm, or stick out your tongue, the point of mass moves along.

To determine if a figure is balanced or not, draw a plumb line from the center of mass to the floor. The body should be supported at this exact point, for example by a foot, by two feet on either side of this point, or by two feet and a hand in a triangle around it.

Figure 2.44. Center of mass

Here we see two standing figures. The one on the left is standing up straight, and the center of mass is located right above a point between the feet. The other manikin strikes a very old-school pose, the contrapost. This is a relaxed pose, where the body weight is shifted to one leg, and the shoulders and hips are tilted. If we draw a line down from the center of mass, it turns out that indeed most of the weight is carried by the right foot.

Figure 2.45. The center of mass moves when the body bends

The center of mass isn't always located at the same spot. Here you can see how it shifts along when the torso and arms move to a side. But as long as it remains above the feet, our manikin won't fall over.

If the center of mass is not supported, the pose conveys motion. This could be a falling motion, or something more deliberate such as running, jumping, or dodging. For example, look at this sprinter, just before and just after the gun fired: