Answer John replies
When illustrating a character in action, it’s important that the action be both believable and energetic. Many artists make the mistake of showing all the character’s action moving in just one direction, which ends up looking flat and stiff. Others put all their focus on just the one part of the body doing the action, without regard to the natural responsive motion required by the rest of the body.
When any part of the body is acting in one direction, another part of the body naturally moves in the opposite direction. This serves to strengthen the action and keep the body in balance. Illustrating this is essential for an action to look both natural and energetic.
Artists can be more successful in their understanding of the body’s motion, actions and reactions by studying the movements of athletes and gymnasts.
As her shoulder moves up, the opposite shoulder moves down. As her punch angles down, her hips angle up. This can create plenty of action.