6 Tension and relaxation
Any form will generally have a combination of tension and relaxation. It’s one of the things that brings life into the form. Keep observing the switch between the two states. Student artists often ask me why their drawings look stiff. One of the most glaring issues I see is that people overlook which areas of their character’s body are tense and which ones are relaxed. They draw hands, legs, the torso and so on well, but everything is almost rigid. If the entire body is tensed then the artwork will look stiff, too.